We are designing a conversational UI. Who offers "VUI" (Voice UI) design guidelines?

Yes. There are several strong sources of VUI (Voice User Interface) / conversation-design guidelines, especially from the major voice-platform vendors.

Best sources

• design.google Probably the best vendor-neutral-ish starting point. Google emphasizes principles such as giving the VUI a personality, understanding conversational context, being brief and relevant, and designing around how people naturally converse.
• developer.amazon.com A very practical set of guidelines covering natural-language interaction, task flows, unexpected utterances, discoverability, testing, and what Alexa should say.
• developer.amazon.com Useful for the actual design process: user journeys, personality, storyboards, prototyping, testing, and iteration.
• developer.amazon.com Particularly useful if you're designing the dialog itself: write for the ear, use contextual questions, conversational grammar, varied responses, and graceful error handling.
• microsoft.com Broader than VUI, but highly relevant if your conversational UI is AI-powered. It provides 18 evidence-based guidelines and design patterns covering initial interaction, ongoing interaction, errors, and long-term use.
• learn.microsoft.com More specifically addresses voice-only interactions, including variation in how users phrase things, volume, and limitations of speech recognition/synthesis.

One particularly good book

Cathy Pearl, Designing Voice User Interfaces: Principles of Conversational Experiences is probably the most directly applicable comprehensive reference. It covers VUI fundamentals, conversational vs. command-and-control systems, speech-recognition implications, multimodal interfaces, testing, and real-world examples.

For your conversational UI

If you're designing a modern conversational UI rather than an Alexa/Google-specific skill, I'd combine:

1. Google's conversational principles for the underlying interaction model.
2. Amazon's voice-design material for concrete patterns and dialog mechanics.
3. Microsoft HAX for AI-specific behavior, uncertainty, errors, and user expectations.
4. Cathy Pearl's book as the deeper VUI reference.

A useful distinction is that VUI design guidelines are increasingly overlapping with "conversation design" and "conversational UX" guidelines. For an AI chatbot that happens to support voice, you generally want the latter as your foundation, then layer VUI-specific rules on top—especially brevity, turn-taking, interruption/barge-in, repair after recognition errors, auditory memory load, confirmation, and multimodality.

When designing a Voice User Interface (VUI) and conversational experiences, several major tech ecosystems and UX institutions provide comprehensive, battle-tested design guidelines. Because voice relies on an aural, linear, and memory-dependent medium rather than visual menus , these guidelines focus heavily on prompt design, persona, error recovery, and multimodal harmony.

The primary providers of VUI design guidelines include:

• Amazon (Alexa Design Guide): One of the most robust and mature resources available. Amazon’s Alexa Skills Kit Design Guide covers conversation design, multi-modal screen integration (for devices like Echo Show), voice user personas, handling interruptions, and accessibility.
• Google (Google Assistant / Conversational Actions): Google provides extensive documentation on designing conversational flows, voice-forward experiences, and multimodal patterns like Interactive Canvas Design which blends voice and immersive visual elements.
• Microsoft (Design guidance & Fluent): Microsoft offers inclusive design principles and conversational AI guidelines focusing on transparency, predictable behavior, and graceful error handling when an assistant mishears or misunderstands context.
• Apple (Human Interface Guidelines - Siri & Audio): While more integrated into their overall ecosystem, Apple provides direction via the Apple Developer HIG on leveraging SiriKit, voice shortcuts, and audio feedback cleanly within apps.
• Nielsen Norman Group (NN/g): As a premier independent UX authority, NN/g publishes deep-dive research articles and heuristic evaluations specifically for VUI, conversational design, and reducing cognitive load in speech-driven applications.

If you'd like, I can share:

• Key VUI design patterns for handling "no-match" or error recovery loops
• How to structure persona and tone for a conversational agent
• The core differences between command-driven vs. open-domain conversation models

Let me know what aspect of your conversational UI you want to tackle next!

Major tech ecosystems and UX thought leaders offer the most comprehensive and authoritative Voice User Interface (VUI) design guidelines. Because building a voice experience requires shifting away from visual layouts to conversational memory, pacing, and earcons, these platform guides serve as the gold standard for design principles.

The primary creators and publishers of VUI design guidelines include:

• Amazon (Alexa Design Guide ): One of the most extensive and mature libraries for conversational design. It covers voice interaction models, multi-modal designs (pairing voice with screens like the Echo Show), accessibility, and building distinct conversational personas.
• Google (Google Design / Assistant Guidelines ): Historically established robust principles around conversational design for Google Assistant and Interactive Canvas. Their core philosophy emphasizes giving the VUI a consistent personality, keeping prompts brief and relevant, and leveraging context.
• Apple (Apple Human Interface Guidelines ): Offers systemic patterns for audio navigation, Siri integrations, and audio feedback frameworks across iOS, watchOS, and homeOS. Apple focuses heavily on privacy transparency, short commands, and contextual awareness.
• Microsoft (Microsoft Design / Conversational AI Guidelines ): Provides enterprise-grade patterns for bots, speech recognition, and cross-device conversational AI experiences, focusing heavily on inclusivity and error recovery.
• Independent UX Authorities (Nielsen Norman Group, Interaction Design Foundation): Publish deep academic and empirical research regarding user mental models, acoustic feedback, and reducing cognitive load in auditory-only displays.

If you'd like, let me know:

• Is your VUI voice-only (smart speaker) or multimodal (voice + screen)?
• What is the primary use case or domain (e.g., customer service bot, in-car assistant, smart home)?

I can share specific dialogue design patterns or error-handling best practices tailored to your project.

For a conversational UI, the field is usually called VUI (Voice User Interface) design, conversation design, or voice experience (VX) design. Several major platform companies and UX organizations publish guidelines:

Major VUI / conversation design guideline sources

Amazon — Alexa Voice Design Guide

Amazon has one of the most mature public VUI guideline sets, covering:

• Conversation flows and dialog design
• Writing for the ear (spoken language vs. written copy)
• Prompt design
• Error handling
• User utterance variation
• Personas and tone
• Multimodal voice + screen experiences

The Alexa design guidance emphasizes designing conversations before implementation and treating voice interaction as a human dialogue rather than a GUI translated into speech.

Google — Conversation Design Guidelines

Google’s guidance is broader than just voice; it focuses on conversation design:

• Designing natural conversational flows
• Creating system personas
• Managing context
• Making interactions feel cooperative
• Handling multimodal experiences

Google frames conversation design as a distinct discipline combining UX, writing, interaction design, and voice UI design.

Apple — Siri Design Guidance

Apple’s Siri-related guidance tends to focus on:

• SiriKit integrations
• Intent-based interactions
• Human-centered phrasing
• Maintaining consistency with Apple platforms

It is generally less of a standalone VUI handbook than Amazon or Google’s materials.

Microsoft — Conversational AI guidance

Microsoft provides guidance around:

• Conversational agents
• Bot design
• Speech interfaces
• Accessibility
• Responsible AI patterns

Useful if your conversational UI is enterprise-oriented.

Nielsen Norman Group — Voice UX research

NN/g has UX research articles and heuristics covering:

• Voice usability
• Conversational interaction patterns
• Designing for human expectations
• Avoiding common voice UX failures

Books commonly referenced by VUI designers

• Voice User Interface Design — one of the foundational VUI design books.
• Designing Voice User Interfaces — practical guidance from a Google Assistant design leader.

Common principles across most VUI guidelines

Regardless of platform, most recommend:

1. Design conversations, not screens

• Start with user goals and dialog flows.
• Avoid simply reading UI labels aloud.

2. Write for listening

• Short sentences.
• Put important information early.
• Avoid long lists unless users can interrupt or refine.

3. Create a consistent persona

• Define tone, vocabulary, personality, and boundaries.

4. Support natural language

• Users will not memorize commands.
• Design for many ways of expressing the same intent.

5. Manage turn-taking carefully

• Know when to ask, confirm, summarize, or hand control back.

6. Handle errors conversationally

• Avoid dead ends like “I didn’t understand.”
• Offer recovery paths.

7. Design for context

• Remember previous turns.
• Use user history appropriately.
• Avoid asking for information already provided.

For a team creating a general conversational UI (not tied to Alexa/Siri/Assistant), I would typically start with Google’s conversation design material + Amazon’s Alexa Voice Design Guide, then add your own brand voice, dialog patterns, and accessibility rules.

• Amazon offers the Alexa Design Guide focusing on voice-first design, multimodal interactions, and persona creation for Alexa skills.
• Apple provides the Human Interface Guidelines for Siri and Audio covering voice commands, shortcuts, and audio integration across Apple ecosystems.
• Google features the Google Design Guidelines for Voice (centered around Google Assistant), detailing conversational design principles, prompt engineering, and user flows.
• Microsoft outlines conversational and voice principles in the Microsoft Design Guidelines for speech interactions and Cortana/bot integration.
• IBM provides enterprise-oriented conversational design frameworks via IBM Carbon Design System and Watson Assistant guidelines, focusing on intent, dialogue state, and fallback strategies.
• Nielsen Norman Group (NN/g) offers independent UX research and Voice User Interface Guidelines regarding discoverability, memory load, and error handling in VUI.

Would you like me to dive deeper into one specific platform's guidelines (like Amazon or Google), or do you need help structuring a core set of VUI principles for your project?

Yes. There are several strong sources for VUI / voice and conversational UI design guidelines. For a conversational UI, I’d prioritize these:

1. Google — probably the best starting point

Google's guidance treats conversation design as a broader discipline than just writing voice prompts. It covers conversation flows, style, prompts, error handling, conversational components, and visual components.

Google also has a particularly useful set of VUI principles:

• Give the VUI a personality
• Move the conversation forward
• Be brief and relevant
• Leverage context
• Use word order and stress to direct attention
• Don't teach users "commands" unnecessarily

Those principles are useful even if you're not building for Google Assistant.

2. Amazon Alexa

Amazon has some of the most concrete VUI guidance available. It covers designing the interaction model, understanding what users might say, response design, conversational flows, error handling, and testing.

Amazon's more recent voice experience fundamentals are also platform-relevant: they emphasize mapping the user's journey, designing personality, storyboarding, prototyping, testing, and iterating.

3. VUI Guide — platform independent

This is worth bookmarking if your product isn't tied to Alexa or Google. It's explicitly designed as a voice user interface guide, with a resource section and a checklist for working through a VUI design. It's open source as well.

4. Cathy Pearl's Designing Voice User Interfaces

If you're looking for something more substantial than a web style guide, Cathy Pearl's book is one of the standard references. It covers VUI fundamentals, conversational systems, speech recognition's effect on design, testing, measurement, and real-world voice interfaces.

5. Classic VUI methodology

The older but still influential Voice User Interface Design by Michael Cohen, James Giangola, and Jennifer Balogh is particularly useful for understanding the foundations of VUI design, including linguistics, psychology, speech recognition, and structured VUI methodology.

For your conversational UI project, I'd use Google + Amazon + VUI Guide as the practical trio, then use Pearl's book for deeper UX rationale.

One important distinction: if your "conversational UI" is chat + voice + visual UI, don't limit your research to VUI. The modern term conversation design is arguably more appropriate because it encompasses the dialogue model, user intent, context, error recovery, prompts, and multimodal presentation—not merely the spoken interface.

Yes. There are several good sources for VUI (Voice User Interface) / conversation design guidelines, although there isn't one universally accepted standard. A 2023 IBM Research meta-analysis reviewed 336 published VUI guidelines and found substantial variation between sources.

Strongest sources to look at

A particularly useful distinction for your project is VUI vs. conversational UI (CUI). If you're designing a conversational UI that may combine voice + text + visual UI, I'd lean toward the Google and Amazon material rather than treating it purely as a speech-interface problem.

If you're building a general conversational UI

I'd use these three as the foundation:

1. Google's conversation principles — for the interaction philosophy: conversational turn-taking, context, personality, brevity, etc.
2. Amazon's voice design process — for the design methodology: user journey → dialogs → storyboard → prototype → test.
3. IBM's meta-analysis — to avoid accidentally adopting one vendor's conventions as if they're universal VUI principles.

One important principle that comes through especially clearly in these sources: don't design voice as a GUI translated into speech. Voice has different constraints—users have to listen rather than scan, working memory matters much more, and the system needs to manage conversational turns explicitly. Google makes this point particularly well.

If you want, I can also compile the major VUI guidelines from Google, Amazon, Microsoft, IBM, Apple, etc. into one consolidated design checklist, organized by things like prompts, turn-taking, errors, confirmations, interruptions, context, personality, accessibility, and multimodal UI.

Major technology platforms and UX thought leaders offer the primary Voice UI (VUI) and conversational design guidelines. Because voice requires a shift from visual scanning to linear, auditory processing , these companies developed extensive documentation to help designers handle persona creation, dialogue flows, and error recovery.

• Amazon (Alexa Design Guide) : Amazon provides the Amazon Alexa Design Guide , which outlines how to design voice interactions, multimodal displays (Echo Show), and physical hardware responses. It covers everything from wake-word behavior to crafting natural voice prompts.
• Google (Google Design & Actions on Google) : Google published foundational principles via Google Design and developer documentation for Google Assistant Conversational Actions . Their guidelines focus heavily on giving the VUI a personality, leveraging context, and managing cognitive load on screens.
• Apple (Human Interface Guidelines) : Apple includes specific audio and spoken-word interaction rules within the Apple Developer Human Interface Guidelines . Their documentation focuses on integrating Voice Control, Siri, and Shortcuts for seamless voice-driven operations.
• Rasa & Conversational AI Platforms : Open-source and enterprise bot frameworks like Rasa's Conversational UI Rules offer great framework-agnostic design rules for handling fallback states, dialogue architecture, and context switching.

Would you like me to share a breakdown of the core principles shared across these guidelines (like error handling and brevity), or are you focusing on a specific platform (like Alexa or a custom chatbot)?

Yes. There are several good sources, ranging from platform-specific guidelines to general VUI/conversational-design principles.

The strongest sources

• Google — Conversation Design / VUI principles. Google has a particularly useful conceptual guide, Speaking the Same Language, which argues that voice interfaces should be designed around human conversational principles rather than simply translating GUI patterns to speech.

• Amazon Alexa — Voice Experience Design. Amazon provides extensive practical guidance covering conversation flows, user journeys, personality, storyboarding, prototyping, testing, and multimodal interactions.

• VUI Guide — general/open-source VUI pattern library. VUI Guide is probably the closest thing to a vendor-neutral VUI design guideline. It covers fundamentals, wording, feedback, user control, error recovery, intents, patterns, and checklists.

• Amazon Multi-Agent Design Guide. If your conversational UI involves multiple voice agents or agents sharing a device, Amazon's newer guide covers invocation, discovery, human-interface behavior, agent transfer, privacy, and security.

If you're designing a modern conversational UI, I'd use these in combination

There is also substantial academic work: one systematic review identified 127 VUI design guidelines across 35 papers, organized into five themes.

My recommendation: don't treat Alexa/Google guidelines as the specification for your UI. Use them as pattern libraries, then build your own design system around concepts such as turn-taking, discoverability, confirmation, interruption/barge-in, error recovery, ambiguity, user control, feedback, memory/context, and multimodal fallback.

If you're designing a voice + screen conversational UI, I can also give you a consolidated set of ~20 VUI principles distilled from Google, Amazon, Nielsen-style usability heuristics, and current conversational-AI research.

When designing a voice user interface (VUI) or conversational experience, several major tech ecosystems and UX institutions provide comprehensive design guidelines, best practices, and foundational frameworks.

The primary organizations and platforms that offer official VUI and conversation design guidelines include:

• Amazon (Alexa Design Guide) : Amazon provides extensive documentation tailored for building voice experiences and skills. The Amazon Alexa Design Guide covers conversation design, persona creation, multimodal integration (combining voice with screens), and handling complex error recovery.
• Google (Conversation Design) : Google pioneered structured frameworks for voice interaction through its Google Assistant ecosystem. Though historical documentation evolved, the core teachings are widely accessible via articles like the Google Design Guide on UI & UX Principles for Voice Assistants , focusing on brevity, relevance, context, and human-like turn-taking.
• Apple (Human Interface Guidelines) : Apple includes specific audio and voice-interaction considerations inside the Apple Human Interface Guidelines covering Siri integration, audio feedback, and voice-activated shortcuts across iOS, watchOS, and macOS.
• Microsoft (Inclusive Design & Cortana legacy) : Microsoft incorporates conversational and voice principles into its broader Microsoft Inclusive Design Guidelines , which address speech-to-text accessibility, multi-modal cues, and graceful error handling.
• NN/g (Nielsen Norman Group) : As an authority on evidence-based UX, the Nielsen Norman Group publishes industry research and UX guidelines on conversational AI, voice search behavior, and reducing cognitive load in audio-only environments.

Are you designing a voice-only (eyes-free) experience or a multimodal (voice + screen) interface? Knowing this can help me share the most relevant dialogue flow and error-handling strategies.