Do you have one?
1. Understanding your current capacity by phase (initiation, requirements, dev, etc) by Role is critical. if you don't have this you are screwed from the start.
2. before you launch each project have you done discovery to understand business and IS hours needed to complete the project? Costs, ROI, CBA, etc. Basically do you understand the full costs (as best as you can at this point) vs. what you are getting?
3. Do you constantly go back to #2 as you complete each phase? If not you might be doing projects that no longer bring value.
4. Do you understand your strategies to help pick the projects regardless of their cost/benefits? For example if your goals are to win market share but all your projects focus on operational improvements you might have a problem?
5. Building off of #4 do you know all your strategies and what percentage you are focused on for each one? 50% operational improvement, 25% win the market, 10% shake up the market, etc.
6. Do you revisit all of the above as market changes? This should be done quarterly at least.
7. Do you understand how bringing in contractors helps your capacity model? It doesn't matter if you bring in 50 java developers but your bottle neck to testing.
8. Does leadership understand all of the above? are they educated and given data to show the above?
That would at least help your discussions.