Laura Quinn, Director of Idealware has released a valuable analysis on three approaches to data integration.  Her site provides articles which help nonprofits decide what software to choose.  Integrating data between different systems is always a sticky challenge, as I’ve experienced in my current role at the Crohn’s & Colitis Foundation as we’ve attempted to integrate our financial, offline fundraising and online fundraising systems.  Laura’s article is a clear summary of integration options.