I tend to agree with Phil and yet disagree. I feel initial development should start out small in a concept mode using isolated data in a strictly development only environment. However, the trick is have not just one or two levels of development and testing but at least four levels where each level of test and debugging is progressively more production-like prior to cutting a new system or maintenance changes over to production.

Granted, that implementing a series of separate server (farms) for Development, Test (1 and/or 2), Sim-Prod, and Production could be very expensive for a small business. However, the heavy production system Phil outlines, is not one of a small business, or at least is not any longer a small business category. And, the firm involved must be willing to invest in providing a more robust data environment in hardware, software and especially in data and code migration and testing policies.