I've been on both sides of this equation: not wanting to be availble outside of "business hours" and also feeling frustrated when colleagues aren't available wh

I've been on both sides of this equation: not wanting to be availble outside of "business hours" and also feeling frustrated when colleagues aren't available when I need them. I view this as an engineering and social process problem: your systems should be reliably engineered such that off hours maintenance or other technical issues are minimized. This gets to the social part: people will be more receptive to off hours work if its a rare occurance.