Dependencies are how you tell Project the order in which tasks must occur. Constraints are how you tell Project if a task must be associated in some way to a specific date. Both can be used to order tasks within your project. However, dependencies are by far the better choice for specifying the order of your tasks. Constraints can be useful, but only for tasks that have a real connection to a given date. This chapter examines dependencies and constraints, when to use them, and how to create and edit them.