You can set up a table where one record = one project and store your Project Titles here. Now you can define a value list that specifies the Project Titles field in this table.
A pair of design suggestions:
Don't use your Project Title field as the key field in any relationships. If you do and then later discover you have to change the Project Title (perhaps it was misspelled), you'll have problems when you change the name in a table and break the link to any related records in other tables. Instead, base your relationships on an auto-generated serial number field.
Since you have many people working on many projects, you have a many to many relationship. The most flexible way to work with this situation is to create a join table that links to both your personnel and Projects tables. If you are unfamiliar with join tables, click the Advanced search link above to search for threads that talk about a "Join Table".