Asynchronous communication (async) is communication that doesn't require both parties to be present or available at the same time — messages are sent, work is shared, and decisions are documented in a way that allows the recipient to respond when it's suitable for them. Email, recorded video, Slack messages, wiki pages, document comments, and pull request reviews are all async communication. The alternative — synchronous communication — requires simultaneous presence: live meetings, phone calls, real-time chat.
Async communication is a conversation with a delay by design, not a broken synchronous one.
Where the Concept Comes From
Asynchronous communication isn't new — written letters have always been asynchronous. But as a deliberate organizational design principle (rather than just a technical distinction), the concept gained traction with the rise of:
Email (1970s-90s): The first widespread async business communication tool. Email created the template: compose a message, send it, receive a response on the recipient's schedule.
Open source collaboration (1990s-2000s): The Linux kernel, Apache, and other major open-source projects were built almost entirely asynchronously by contributors across the world in different time zones. This demonstrated that complex, high-quality work could be coordinated without synchronous presence.
Distributed work (2010s): Companies like Automattic (makers of WordPress), Basecamp, GitLab, and Buffer built fully remote, globally distributed teams and developed explicit async-first communication norms. Basecamp published Remote (Fried and Hansson, 2013) and It Doesn't Have to Be Crazy at Work (2018) making the cultural case for async work. GitLab published a comprehensive async-first handbook.
COVID-19 (2020): Remote work became mainstream overnight. Async communication practices spread rapidly as teams that had been synchronous by default were forced into distributed setups.
The concept crystallized from a technical description (messages that don't require simultaneous presence) into an explicit organizational philosophy: async-first communication as a default, with synchronous communication reserved for what genuinely requires it.
Sync vs. Async: The Core Distinction
| Feature | Synchronous | Asynchronous |
|---|
| Presence required | Both parties at the same time | Each party responds when available |
| Examples | Video calls, phone calls, in-person meetings | Email, Slack messages, Notion docs, recorded video, PR comments |
| Response time | Immediate | Minutes to days |
| Record created? | Requires deliberate note-taking | Inherent record in the message thread |
| Time zone sensitivity | Highly constrained | Independent of time zones |
| Depth of thought | Limited by real-time pace | Allows considered, researched responses |
| Best for | Complex real-time collaboration, emotional conversations, quick clarifications | Status updates, detailed decisions, documentation, reviews |
Neither is universally superior. The question is which mode fits the communication need.
How Async-First Organizations Work
Async-first doesn't mean "never have meetings" — it means starting with async and escalating to sync only when necessary.
The async default:
Before scheduling a meeting, ask: could this be a document, a recorded video, a Slack message? Most status updates, one-way information sharing, reviews, and low-urgency decisions can be handled asynchronously.
Written over verbal:
Async-first organizations write things down. Decisions, context, rationale — documented and searchable, not delivered in meetings that produce no artifact.
Meeting exceptions:
Some situations genuinely benefit from synchronous communication:
- Complex collaborative problem-solving that requires real-time feedback loops
- Sensitive interpersonal conversations (feedback, conflict resolution)
- Brainstorming sessions that benefit from rapid back-and-forth
- High-urgency situations requiring immediate coordination
Response time norms:
Async requires clear norms about response time expectations. "Respond within 24 hours on Slack" establishes async norms; expecting immediate responses to Slack messages re-creates synchronous pressure without the meeting.
A Worked Example
Two engineering teams — one sync-heavy, one async-first — handle a product decision differently.
Sync-heavy team:
The engineering lead wants to decide on a new deployment approach. Schedules a 1-hour meeting with 8 engineers. 30 minutes are spent getting everyone on the same page about the current state (information that could have been shared in advance). 20 minutes are spent in a decision that requires 3 people to understand deeply; the other 5 are listening. 10 minutes produce an action item list that isn't written down coherently. Three people leave uncertain about the decision. A follow-up is scheduled.
Async-first team:
The engineering lead writes a 500-word RFC (Request for Comments) document: current state, proposed approach, alternatives considered, open questions, and a decision deadline of Friday. Engineers comment asynchronously over 3 days at their convenience, adding expertise from their own areas. The lead synthesizes comments and updates the document with the final decision. The decision is documented, searchable, and the context for why it was made is preserved.
Total time:
- Sync meeting approach: 8 people × 1 hour = 8 hours + follow-up
- Async RFC approach: Engineering lead: 1 hour to write; 8 engineers: 15-30 min each to read and comment = 3-5 hours total
The async approach produces a better decision (more considered input from each contributor), a documented outcome, and uses significantly less total time.
Async Communication Tools
| Tool type | Examples | Best for |
|---|
| Long-form writing | Notion, Confluence, Google Docs | RFCs, decisions, documentation, processes |
| Threaded messaging | Slack, Teams, Discord | Project updates, questions, short decisions |
| Video messaging | Loom, Vidyard | Walkthroughs, presentations, feedback |
| Project management | Linear, Asana, Jira | Task tracking, sprint reviews, status |
| Code review | GitHub PRs, GitLab MRs | Technical decisions, code discussions |
| Email | Gmail, Outlook | External communication, formal decisions |
The tools matter less than the norms: async communication requires that teams agree on what goes where, what the expected response time is, and what belongs in async vs. sync.
Common Misconceptions About Asynchronous Communication
"Async communication is slower."
Async communication is slower for a single exchange — you don't get an immediate response. But it's often faster for decisions that would otherwise require scheduling a meeting across multiple calendars (which might be days away), then conducting the meeting, then waiting for action items to be circulated. For complex decisions, async produces better outcomes in less total time.
"You can't build team culture asynchronously."
Culture-building is harder async, but not impossible. Async-first companies (Automattic, GitLab, Basecamp) have built strong cultures with predominantly distributed teams. It requires deliberate effort: async social channels, virtual coffee chats, documented values and norms, and occasional in-person gatherings for relationship building.
"Async is just for remote teams."
Async-first communication improves outcomes for co-located teams too. Written decisions are searchable; meeting notes aren't recalled consistently. Async enables deeper thought — people can research before responding. Even co-located teams benefit from async for decisions that don't require real-time collaboration.
Related Concepts
Knowledge silo: Async communication, when documented, creates shareable artifacts that break knowledge silos — decisions and context are accessible rather than locked in meeting memories.
Single source of truth: Async documents serve as authoritative references; sync meetings rarely do.
Context switching: Async communication, when handled in batched sessions rather than continuously, reduces context switching costs compared to always-on synchronous chat.
Deep work: Cal Newport's deep work concept — uninterrupted focus on cognitively demanding tasks — is enabled by async communication norms that reduce real-time interrupt pressure.
Frequently Asked Questions
How do you handle urgent situations asynchronously?
Most "urgent" situations aren't actually urgent — they feel urgent because of social pressure to respond immediately. Defining actual urgency (production down, customer emergency, safety issue) and reserving synchronous communication for those cases creates clearer norms. For genuine emergencies, phone or video call is appropriate. For "urgent but can wait 2 hours," async works fine.
How do you establish async norms in a previously sync-heavy team?
Start with small changes: write a decision document before the next meeting and share it 24 hours ahead; record a Loom video instead of scheduling a meeting; set explicit response-time expectations in Slack channels. Build the habit gradually rather than requiring an overnight cultural shift.
What's the right ratio of async to sync communication?
There's no universal ratio. GitLab operates at approximately 80-90% async; many office-based teams are 70-80% synchronous. The question isn't hitting a specific ratio but shifting the balance toward async where it genuinely fits and reserving sync for what requires it. A team that asks "why are we meeting?" before every meeting is practicing async-first regardless of the percentage.
Key Takeaways
- Asynchronous communication doesn't require simultaneous presence — email, Slack, docs, recorded video, and PR reviews are async; meetings and calls are synchronous.
- Popularized as an organizational philosophy by remote-first companies (Automattic, GitLab, Basecamp) in the 2010s and broadly adopted post-COVID-19.
- Async-first means starting with async and escalating to sync when genuinely necessary — not eliminating meetings, but reserving them.
- Creates records: async produces searchable, documented artifacts; synchronous meetings rarely do without deliberate note-taking.
- Requires explicit norms: response time expectations, which tool for what, and clarity on what escalates to sync.
- Not slower: async reduces meeting overhead and produces more considered decisions for complex topics, despite slower individual exchanges.
Conclusion
Asynchronous communication is not primarily a technical choice — it's an organizational design choice about when and how teams share information, make decisions, and collaborate. Async-first teams create a written record of how decisions were made, enable deep work by reducing real-time interrupt pressure, support distributed and time-zone-distributed work, and often produce better decisions by allowing more considered, researched responses. The shift from sync-default to async-first requires explicit norms, good writing culture, and willingness to escalate to sync for what genuinely needs it — while resisting the reflex to schedule a meeting for everything else.
Try WebSnips free — as your team creates async documentation and decision records, clip and organize the external research and references that inform those decisions into shared collections, making your async knowledge base richer and more searchable.