A good technique to master and manage your project scope is the use of a Work Breakdown Structure (WBS).

What is a WBS?

Wikipedia definition:

A work breakdown structure or WBS is a fundamental project management tool. A common technique for defining and organizing the total scope of a project, is to use a hierarchical tree structure. The first two levels of the WBS (the root node and Level 2) define a set of planned outcomes that collectively and exclusively represent 100% of the project scope. At each subsequent level, the children of a parent node collectively and exclusively represent 100% of the scope of their parent node. More generally, outside of it's original mil standard and PERT/CPM context, a WBS is a mapping from one level of system specification to another, for example a requirements cross reference matrix mapping functional requirements to high level or low level design documents. A well-designed WBS describes planned outcomes instead of planned actions

In Microsoft Dynamics Sure Step Methodology WBS structures are included. The planning tools (MS Projects) are also based on the available WBS structures. The only thing not there is a nice visualization of the tree structure. On the web I found a nice tool called WBS Chartpro. You can use this tool to create WBS structures but also it can create a WBS automatically based on a MS Project file.

WBS Chart Pro can be used to generate WBS charts directly from existing Microsoft Project plans. WBS Chart Pro uses the Outline created in Microsoft Project to generate a hierarchical view of the data. A WBS toolbar button can be installed into Microsoft Project for easy transfer of data. As you organize and change your project in Microsoft Project, a WBS chart of that data is only a button away.