How many projects is too much?

Frank Patrick has an interesting question up about how many projects can a project manager handle? He's inviting comments from other people.

I know that there have been times in my career when I have reached that limit - and motored on past it. Some people reach that sooner than others, and everyone reacts differently when they get there.

Personally I found that I relied too much on my personal ability to stay on top of everything, keeping it all in my head so to speak. When I reached my limit, my projects started getting out of control, and I couldn't seem to get on top of them.

The answer (for me) lay in being completely disciplined in how I manage projects, whether handling one or many, mainly because you never know when you will reach your limit. That discipline meant that I never lost my way, and when I was overloaded, I could more easily share the workload with my team and other project managers.

Another key was learning when to 'push back', and let my boss know that I was sceptical of my ability to handle more work. That often helped, because then we could negotiate what I needed to do, and he could help me by re-prioritising internal projects or working out where a client could be accomodated differently, or handled by someone else's team.