Assumptions and Risks are interrelated, so manage both diligently.

There is absolutely nothing wrong with making an assumption that fundamentally reduces project risk… provided that all the project stakeholders are aware of it, and in agreement with it.  Undocumented or ambiguous assumptions can jeopardize an otherwise good project plan.  One of the most frustrating things to deal with as a key project stakeholder is discovering late in a project’s life cycle that the project was derailed due to inadequately communicated assumptions.  Fortunately, this type of situation is fairly easy to avoid.  There are some sound and fairly simple steps for determining the validity of assumptions (i.e., whether they should be categorized and dealt with as risks), and ensuring that they are properly communicated and accepted by key project stakeholders.  This topic is covered in my book “Project Risk Management: A Practical Implementation Approach” and should be taken to heart – for “doing more with less” does not mean to do less and end up with a project outcome that is unacceptable.