(FORTUNE Small Business) – I have a temper. No, that's not quite true. I have a very big temper, the kind that every six months or so builds up and crashes down on people with a cascade of curses. Over the past eight years I've smashed two phones, opened a door so hard that I shattered the picture frame opposite, and punched a hole in the wall. Some piece of particularly dismal news sets me off, usually a customer's complaint. My last outburst proved so bad that the object of my scorn, a customer service agent, left my office in tears and couldn't bring herself to return to work for two days.

Needless to say, that kind of rage is hardly a useful management technique. Afterward I find myself fractured and unfocused. I go home and am irritable with my family. The poor employee subjected to my tirade usually can't work for the balance of the day and certainly doesn't change for the better. In other words, it doesn't work. When I'm clear-headed, I admit that most mistakes are made either because we haven't provided adequate training or because folks just commit an honest error. That is particularly true of late, as our family-owned plastic-bag-manufacturing company has tried to shove through more sales without expanding staff. We've pushed people to—and maybe beyond—their capacity. If employees know that admitting errors means they're going to be lambasted, it is likely that bad news won't reach me. I saw that dynamic at work recently when a manager sidestepped telling me about problems with the inks we use to print our bags. I like to think of myself as a good and decent person—don't most of us?—and I'm tired of scaring people and doubly tired of how my temper wrecks me.

So I've changed my ways. After terrorizing my customer service agent over a pricing decision she made, I decided to stop unloading on my employees. I sought out a business coach, whose anger-management advice included having me count to ten before responding, and going for walks when the impulse to rage grew. I actually managed to get through a difficult period recently—a production glitch on one bagmaking machine cost us $25,000 in claims—without raising my voice.

That isn't to say I've capped my temper like a dried-up oil well. In fact, I've come to accept that expressing anger can be useful in business, a venting I call "strategic anger." Unfortunately, sometimes the only way to get people to act is to raise your voice and pound the table. For instance, a key supplier of ours recently failed to deliver on time the specialty plastic we needed. No amount of cajoling could get the supplier to deal with the bottlenecks, which threatened to alienate one of our fastest-growing accounts. Finally, I unleashed my pent-up rage. Two months later we have a 30-day supply on hand.

The trick with anger is knowing when to let fly. My normal tirades were delivered too quickly, without first resorting to other options, such as a friendly chat. Today I try to make sure I exhaust all possibilities before unleashing the furies. Not that I always explode. When one large customer told us earlier this year that it planned to cut back our volume, even though it had no complaints about us, I allowed a sense that I was angry to creep into the conversation. The result? The purchasing agent apologized, and our sales remained where they were. Mind you, I can't just turn on some tap of artificial anger at will. My temper is a permanent part of who I am—for better or for worse. I've just gotten much more adroit at knowing when to let it have its day and when to count to ten.