It’s law firm arrival season. The postbar adventure vacations have been tucked into Instagram folders. The first law school debt payments loom. And visions of all-night doc reviews now dance feverishly across imaginations that only a year ago were wooed for their high-performance potential. As they start down this road, here are seven things I’d like the new group of first-year asso­ciates to keep in mind:

For Most, This Will Be Short-Term Employment. If the past is prologue, about one-third of the starting class will have left by the end of their third year; two-thirds of your class will be gone within six years. This isn’t personal; the structure relies on regular departures of associates, sometimes voluntary, sometimes not. For the new lawyers, this means that you’re in charge of your careers. The old paternalistic, just-excel-and you-shall-be-automatically-rewarded game is over. Now you have to decide what you need to learn while you’re at the firm and manage your time accordingly. This regimen is a neat fit for our ironic age: Put down roots and expect to be uprooted.

You Have Two Masters. At the firm, you’re expected to heed your supervisors, be they partners or more senior associates. Ignore them at your peril. But the bigger prize is serving the clients. At first, you won’t be in their company; alas, you may leave without having met one. But eventually—somewhere—you will have your own. Develop the habit of learning your clients’ needs and try to meet them. Do they really require the journal-quality memo and the 105 billable hours it took last week to produce? Or will a single page with five dependencies and one judgment suffice? Ask.

Seek A Mentor and, if you’re serious about staying, a sponsor. Many firms are better now at connecting their juniors with partners who will try to bring them along. But given the internal pace, the personnel churn, and the fact that not every partner is capable of teaching best practices—or teaching at all—you must be prepared to search for your own. Interpersonal chemistry is important, of course, but find the ablest mentors you can, those who will challenge you even as they’re imprinting their habits on your career. If you’re determined to stay at the firm, you will need a sponsor, too. These are partners who will try to advance your career. These folks are hard to find, and most associates won’t acquire one at their first firm. If you wake up as a sixth-year and you can’t name your sponsor, it’s past the time to take those calls from the recruiters.

Don’t Trash The Brand. I receive announcements every week about 45-year-old lawyers taking new positions in government or business that include mentions of their brief stints as associates at Cravath or Latham or S&C (or one of a hundred other firms). This is the halo effect that comes from putting in a little time at one of these fabled places. The assumption is that if you cleared their screening process, you must be pretty good. This is valuable currency, and one you don’t want to devalue for sport. (If you doubt this, check around for lawyers bragging about their time at Howrey or Thelen or Brobeck.) These merit badges will follow you, for good or bad, for the next half-century. That’s worth keeping in mind when deciding whether to tell the world that this or that partner is an officious jerk.

Help Others. You’ve joined a profession and not, for the moment, an industry. Part of your responsibility is to help provide legal services to those people and causes that otherwise couldn’t afford them. That’s a serious obligation. If you fulfill it, you will feel better about yourself in the morning. You also will learn some things about practice and life that you otherwise would not. A corollary point: There are people working at the firm, in a variety of roles, who do not have your credentials. They contribute to your success; some will know things you don’t. Treat them with respect.

You’re Good And You’re Lucky. It’s an accident of timing that you’re beginning work this autumn and not suffering through the doubts of a deferred start date. As the man says, you didn’t build this situation alone. So be mindful of your good fortune and use it not only to pay down your debt but as an antidote to arrogance, which is unbecoming at every level.

Find Work You Love. If it’s at your firm, fine. If not, go elsewhere and do it.