Williams, 1. MS Project defines “Critical” tasks as those incomplete tasks with Total Slack <= 0. (You can increase but not decrease this threshold in the advanced options.) The collection of “Critical” tasks represents the true Critical (logic) Path under some very limited conditions; e.g. only one calendar, no constraints, no deadlines, no resource-leveling, no out-of-sequence progress. 2. Assuming you’ve met other requirements of good scheduling practice (e.g. no “manually-scheduled” tasks, no inactive tasks, no logic on summaries, no logic open ends), then you should be able to define the Critical Path as the driving logic path to the project completion milestone. In MSP 2016 you can identify this path using the Task Path bar styles for “DrivingPredecessors.” It works fairly well for simple projects but is unreliable in the presence of logic that is not Finish-to-Start. It also fails in the presence of out-of-sequence progress and does not penetrate cross-project links (in linked master/sub-projects). If you need, here’s a Macro for Filtering based on “Task Path” in Microsoft Project: https://wp.me/p6CCB4-km.