The progression of events that lead to a baseline is also illustrated in Figure 22.1 . Software engineering tasks produce one or more SCIs. After SCIs are reviewed and approved. they are placed in a project database (also called a project library or software repository and discussed in Section 22.2). When a member of a software engineering team want to make a modification to a baseline SCI, it is copied from the project database into the engineer's private work space. However, this extracted SCI can be modified only if SCM controls (discussed later in this chapter) are followed. The arrow in figure 22.1 illustrats the modification path for a baseline SCI.