A project is made up of one (or more) KDD streams. A KDD stream represents a series of tasks from the different stages of the KDD process. The tasks, represented by nodes, are linked together so that data flows between the stages of the stream.
WITNESS Miner opens a new project whenever you start the application; the workspace is blank and the project is untitled. From this stage, you may either open an existing project, or save the untitled blank project with a new name.
If the workspace already contains a project, you can open a new project in one of two ways:
Click on the new button 
on the standard toolbar.
Alternatively, select the new command from the file menu.
WITNESS Miner prompts you to save the current project before opening a new project.