What does it take to make an application support multiple customers? Carl and Richard talk to Paul Stovell about his work making multi-tenant applications. As with most things, making multi-tenant apps is more complicated than it seems! Paul talks about making architectural decisions around separation between various customers - do they each get their own database? What about web server and/or app-pool? What about customizations and deployment. Do customers get new features immediately, or do they have the option to wait? How does the cloud impact your decision making? It's a complicated subject with a variety of trade-offs!