Not long ago, I found myself under the gun. A story I had assigned to a freelance writer needed a big overhaul. Because of another urgent project, I couldn’t dig in and revise it myself. The quickest fix would be a brand-new article, so I turned to one of my most reliable contributors. Could she possibly turn in a story I’d assigned a little early? She agreed, and her article needed no revision. It reminded me why other editors often tell me they love her—and why self-employed pros like this writer seldom find themselves short of work. It’s not just that they’re good at the work they do. They know how to make clients want more of them.

I’ve hired many freelancers and consultants over the years at past corporate jobs and now for my two writing and editorial services businesses, Elaine Pofeldt LLC, where I handle projects on my own, and El El Enterprises, where my partner Elizabeth MacBride and I take on larger contracts together. I’ve hired writers and designers, web developers and market researchers. Some always have a full slate of work, while others operate in a state of ongoing financial desperation. Here’s what I’ve noticed about the ones who stay busy, through booms and busts.

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The best freelancers focus on long-term relationships. The writer who did the speedy turnaround for me could have said, “Yes, I can help. I’ll have to delay another client’s assignment, so can you pay a rush fee?” But pros like her recognize that there’s more long-term value in helping out in a pinch than in trying to squeeze a few more bucks from an assignment. The next time I have a great project, she’ll be top of mind.

They have a sixth sense for when clients are crazy-busy. The most successful independent pros pay attention when a client says that a new initiative is devouring all her time, or his daughter’s wedding is coming up next week. That’s when they offer extra help. It can be as simple as checking on information the client will need the following week. Savvy independents also recognize that this is no time to add to the client’s workload. If they need help tracking down a lost invoice that week, they’ll get the help they need from someone else at the company.

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Folks who aren’t sensitive to clients’ time pressures are often the ones who find themselves short of work. Recently, one of my retainer clients was swamped with preparations for a big event and asked me to interview a technology consultant the company was thinking of hiring. The discussions with the consultant were progressing nicely, but two weeks before the event, I had to slow the pace of our conversations because the client had no time to talk with me. Impatient, the consultant contacted my client directly to speed things up. Not welcoming this email when he was swamped, my client pulled the plug on the hire. End of deal.