Multiple printed circuit board (PCB) application programs simultaneously execute on a computer. Each application stores data regarding a PCB design in a separate database. The databases are based on compatible data models such that each application is able to receive data from other applications and understand what is to be done with that data. When an edit to a PCB design is made by an application, data for the edit is stored in that application's database. The data for the edit is also automatically provided, via a message server program, to other PCB applications. Each PCB application then stores that edit data in its own database.