Pensions and retirement

Lately I've been thinking about pension funds. (This is partly due to examining the art buying efforts of the British Rail Pension Fund in my research.) There was an interesting article by Lowenstein about why US municipalities are being hamstrung by high pension obligations in the New York Times (here), with quite critical letters pointing out that in the case of teachers, they were trading lower salaries for higher pensions later, and that states and municipalities had been essentially shorting their pension funds, contributing less than they should have due to... let us say overly optimistic assumptions about investment returns (letters here). So this has gotten me thinking about the situation for nonprofits, particularly in the arts.