[hga]

Well, it's implied that we're talking about hiring more workers. For an established firm, there are many options:

Leave money on the table. We're all familiar with companies that have died from expanding beyond their long term prospects or a short term down turn.

Get more out of your current workers; plenty are willing to work overtime for the usual compensation (obviously I'm talking about non-exempt workers).

Hire part-timers and/or contract workers.