Q: I would like to convince my boss that I should have more flexibility in my work. More specifically, I'd like him to authorize some flex hours and give me permission to work from home when I think it's appropriate. How can I make my case?
A: Know what you want, understand his possible concerns and develop solutions in advance.
The inner game
Flexibility is a much-sought-after feature in the workplace. However, since it's become more common, most bosses can easily think of cases in which it hasn't worked out, and these can overshadow the many successes. To address this, spend most of your planning time looking at your ideas from his perspective.
What are the concerns that a rational boss might have? He may be worried that you won't be accessible to him or your teammates. He might like predictability or prefer face-to-face interactions. Using your experiences with him, make as complete a list as you can. Be forewarned: this activity may cause you to get frustrated or defensive, as though he actually were raising these concerns. If this happens, learn from it so that it doesn't show up when you actually discuss your proposal.
Now think about the benefits — for him, not you. If that doesn't come easily, you definitely have some thinking to do.
The benefits to the company could include your availability during nonstandard work hours; for example, evenings or weekends. Having an even more satisfied and loyal employee is good, too, but you don't want it to sound like blackmail to earn your loyalty.
Take your co-workers into consideration next, and the effects on them day-to-day. Will the changes you propose put more burdens on them or cause any resentment?
Finally, think about yourself. Exactly what would you like — what does "some flex hours" mean in practice? How would you determine that it's "appropriate" to work from home? Also be able to express the reasons that this is important to you.