Constraints are simply the things that might interfere with creating and delivering a communication, things over which you have no control. They may include, but are not limited to:

• Preparation time: A communication may need to be done very quickly, even if it’s a formal report or a communication that normally requires more preparation time than an email.
• Delivery time: A communication may need to occur at a specified time, even though that time is not good for all members of the organization.
• Cost: Cost may determine how/if a document is printed, emailed, or mailed.
• Format expectations: The group or organization may have specific format expectations to which you need to adhere, even though the format may not be optimal for the particular communication.
• Available technology: Your audience’s available technology and/or comfort with using technology may determine your choice of medium.
• Technology breakdown: The multiple ways in which technology can malfunction often result in quick changes to the nature and delivery of a communication.
• Available distribution channels: You may be constrained by having to use a specific medium for a specific type of communication, to stay in keeping with the organization’s culture.

The main thing to keep in mind when planning a communication is to be flexible, and have a backup plan in mind to deal with constraints.