This topic was discussed in a PS Village meeting I attended in Atlanta. The participants are service company executives and many wanted to know how everyone else is tackling the enterprise software integration challenge in a SaaS world.

Here are a collection of tips and tricks based on the meeting and our own experiences:

• Integration SaaS software with other SaaS software is pretty easy. You pretty much have no limitations other than the underlying data exchange possibilities.
• Integration of SaaS software with on-premise solutions poses more of a challenge and higher risks. This is because most on-premise software do not offer good integration points and run behind the firewall.
• For any integration avoid reading or writing directly to the database; whatever the application type. Direct database calls is the number one reason why best of breed integrations have had such a bad rap. Direct database reads and writes may break when any of the software applications is upgraded. salesforce.com (the company that made SaaS a commerical success) is a very good example of this. By provided great integration interfaces since its very early versions, and maintaining backward compatibility for those functions, salesforce.com integrations from even 8 or 9 years ago still work today!

Another interesting conversation was around how salesforce.com manages upgrades. Salesforce.com upgrades its entire uses base at once (in a matter of a few days all salesforce.com servers are upgraded to the new version). When a new function is available, the user is given the choice of upgrading to get the new function or staying with the old interface. The upgrades never break existing integrations.