Synchronous vs. Asynchronous Communication

8 minutes, 10 links


Updated March 23, 2023

You’re reading an excerpt of The Holloway Guide to Remote Work, a book by Katie Wilde, Juan Pablo Buriticá, and over 50 other contributors. It is the most comprehensive resource on building, managing, and adapting to working with distributed teams. Purchase the book to support the author and the ad-free Holloway reading experience. You get instant digital access, 800 links and references, a library of tools for remote-friendly work, commentary and future updates, and a high-quality PDF download.

Thanks to the internet, written communications are accessible and aren’t subject to the limitations of physical presence, serendipitous encounters by the seltzer machine, or inconvenient taps on the shoulder.Juan Pablo Buriticá, remote engineering leader*

Before looking into the specifics of various communication channels and tools and how they should be used, it’s important that we understand the difference between the two basic modes of communication that can make distributed teams successful:*

Synchronous communication happens when messages can only be exchanged in real time. It requires that the transmitter and receiver are present in the same time and/or space. Examples of synchronous communication are phone calls or video meetings.

Asynchronous communication happens when information can be exchanged independent of time. It doesn’t require the recipient’s immediate attention, allowing them to respond to the message at their convenience. Examples of asynchronous communication are emails, online forums, and collaborative documents.

This distinction is helpful, but it’s not enough to plan communication for distributed teams. How do you decide which kind to use, and when? Some channels, as we’ll see below, could be used in either manner. The common refrain for remote work is to be “default asynchronous,” but that advice is fairly hard to parse: Are we supposed to never talk anymore? Are video calls now obsolete? This line of thinking takes a narrow view of what works in distributed teams while ignoring the details of how and why different channels are more or less effective, along with individual variance in communication capabilities and preferences.

One framework that some remote teams have used to figure out how and when to best communicate is media richness theory.

In media richness theory, various forms of media are characterized by the nature of information sent over available communication channels.* Lean media like email have a slower interaction rate, fewer visual or auditory cues, and are better suited for when precision is needed. Rich media like face-to-face conversation convey multiple and simultaneous cues—like facial expressions and tone of voice—that allow for immediate feedback, have a personal focus, and enable the use of natural language, which is better suited to conveying concepts or more abstract ideas. The theory was introduced by Richard L. Daft and Robert H Lengel in the mid ’80s (and later joined by Linda Klebe Treviño).

Media richness theory predicts that people will use communication channels based on how communicative they are, but it does not take into consideration other factors, such as relationship growth and maintenance over time. It also posits that anyone can objectively determine what communication channel is more effective depending on the purpose of the communication. For example, if you aim to reduce uncertainty in a situation where more information is needed, you should use email, which has a slower rate of interaction and higher precision. A face-to-face conversation, however, should be used to reduce equivocality, a situation open to more than one interpretation. But since this theory was developed before the invention of modern communication channels like instant messaging and the enrichment of written text with interactivity, it is now a bit outdated.

Unlock expert knowledge.
Learn in depth. Get instant, lifetime access to the entire book. Plus online resources and future updates.

Reaching Common Agreement Is Key to Remote Communication

In 2019, Kumi Ishii, Mary Madison Lyons, and Sabrina A. Carr revisited the media richness theory by validating its applications in modern communication channels (for example, text messaging). They found that individual use of media can have an impact on its effectiveness—it isn’t as simple as objectively letting the need to reduce uncertainty vs equivocality determine the right medium. Factors like formality, concurrency, organizational context, experience with the topic or medium, and the negativity of the message also bear considering, because they can influence the perceived effectiveness of a channel.

Media synchronicity theory posits that any communication medium has five different capabilities in support of the conveyance of information (making it understandable), and the convergence of understanding (reaching a common understanding). These factors are the immediacy of feedback, parallelism, symbol variety, rehearsability, and reprocessability.*

Immediacy of feedback is how quickly people can reply or provide feedback, and how bidirectional the feedback is. A forum post without comments has low immediacy and is largely one-directional.

Parallelism is the number of simultaneous conversations that can happen (also known as the “width” of the medium). A telephone call has low degrees of parallelism, whereas chat has a high degree of parallelism. The more parallelism present, the harder it becomes to monitor and coordinate conversations.

Symbol variety describes the number of ways information can be communicated (also known as the “height” of the medium). This can include verbal and non-verbal symbols (actual crying vs 😭). A lack of symbol variety can have a negative impact on social perceptions in communication.

Rehearsability is the extent to which the media enables the sender to fine tune the message before sending; it’s how “editable” the medium is. Email is more rehearsable than video chat, for example.

Reprocessability is the degree to which a message can be reexamined or processed again within the context of the communication event. Written, asynchronous channels are more reprocessible than synchronous calls and meetings.

Media synchronicity theory considers the development of new media, like collaborative software and instant messaging, and is supported by studies on global collaboration of software development teams. While we don’t expect remote teams to try to directly apply all the aspects of this theory to their communication plans, there’s one important takeaway from the theory that supports what we’ve seen in our own experience.

importantIshii, Lyons, and Carr found that the “best” medium depends on which communication needs are more important for a given situation on a specific team. Most tasks in knowledge work require individuals to properly convey complex information, and to converge on shared meanings. Choosing a single medium for any task may be less effective than using a set of media that the group chooses depending on the process. A team can use email to convey the status of a project externally, and an issue tracker to converge on the understanding of the individual state of the tasks. Success in distributed environments requires that teams come to an agreement about how tools and communication practices will be used within the group.

Compatibility of communication and collaboration tools includes a common agreement and definition on how the tools should be used; for example, commitment from all team members to answer emails in due time, or being logged in to IM whenever available for communication. A common agreement on communication practices is also important, for example, when deciding who should be present in which meetings, where to store important decisions, and whether to inform the whole team about decisions made privately, for example, in IM discussions.Tuomas Niinimäki et al., Journal of Software*

importantWhile asynchronous communication provides a wealth of advantages for remote teams—reducing distractions, increasing focus time, and providing centralized, written documentation that helps keep everyone aligned—it shouldn’t be presumed to be the sole or default mode of communication. Successful remote teams intentionally choose when, how, and why they communicate asynchronously, and diverge from that when it’s important for them to connect in real time.


Presence is the state of being synchronously available for collaborative activities that need to happen in real time. In co-located companies, this means being physically in an office. In distributed teams, presence usually means being available to meet with other people rather than doing individual work.

cautionOne of the most harmful behaviors that can surface in a distributed team is the constant expectation of presence. If employees are expected to always be on email or in a group chat to stay informed, it impacts their ability to do focused work, which is a required component of knowledge work and can be in direct opposition to virtual presence. If someone can’t ignore their email for two hours because their company has a culture of being always on email, their ability to do their work may suffer, which impacts the team’s collective productivity.

Since knowledge workers oscillate between highly collaborative modes and highly focused modes depending on the task at hand, balance becomes key. Distributed teams that want to be effective across time and space will seek this balance and communicate in ways that neither require constant attention, nor create frequent interruptions for employees.

You’re reading a preview of an online book. Buy it now for lifetime access to expert knowledge, including future updates.
If you found this post worthwhile, please share!