Anticlue

Deploying a system Phased vs Bang

Oh the big bang approach, one has to hate it. I remember my first big bang approach a couple of years ago. At the same time we replaced the hospital registration system, interface engine, and implemented a clinical repository. It was several weeks in June, and during that time I got reassigned from the night shift to the day shift. We were staffed for the bang, had a team of consultants on site, IS support was around the clock. People where positioned on the floors. In house registrations were manually transferred from one system to the new system. Oh it was an experience. It has tainted my attitude towards Big Bang implementations.

If I have a preference, and I will strongly argue my position, I like phased implementations. It keeps the deployment manageable. The resources are dedicated to the department or system at hand, not thinly spread across the board. The risk factor is less simply by not implementing the all inclusive solution. One can carefully maintain monitors and trouble shooting is simpler. Plus by phasing in solutions, skeptics convert to true believers.

The only advantage in the big bang is that it gets it all done at once. However the support after live is probably longer than the phased implementation.