I met Austin Fragomen in 2000 when I interviewed to join the firm. I was eager to work there, and more than a little bit intimidated—even then, we were the world's top immigration firm, and Austin's name was on the building.

The interview was terrific. Austin invented modern immigration practice; he's introduced the industry to a number of innovations that are part of today's standard practice. He's a giant. But he's also a surprisingly soft-spoken, thoroughly engaging genius. He listened to me talk about myself: my life, my cases, what I was looking for in a firm.

He listened.

Since then, I've admired his ability to listen above his many other very fine qualities. Later, when I began to work with him directly, he listened to my opinions about our clients and our practice, took them seriously, and congratulated or corrected me as my thinking merited. He obviously takes the same care with clients and works tirelessly to help them solve the challenges they entrust him with. He becomes their business partner—a trusted advisor.

Listening seems like such a simple thing, but it's not. It's a skill that's acquired through practice and attention. It's rare. To listen: It's the best lesson Austin taught me.

Careful attention and receptivity helped him reshape the practice of immigration law. After the firm tackled an unpredictably large influx of cross-border work involving Hong Kong immigrants in 1997, Austin perceived untapped potential in his field—he was the first to realize that immigration was going to scale astronomically as globalization accelerated. And he built Fragomen around that growth, project by project, leading the firm through a worldwide expansion. A less observant lawyer would have missed such an opportunity. A less skilled lawyer would have failed to exploit it.

He also founded the American Council on International Personnel—the first trade organization for businesses that hire foreign workers. Under Austin's leadership, this organization, now part of the Society for Human Resource Management, grew significantly.

His passion for, and dedication to, his craft is inspiring. I worked side-by-side with Austin on a disruptive episode involving a radical overhaul in the Department of Labor's immigration process, known as PERM, which became effective in 2005. We had to reinvent the way we worked with our clients overnight. Austin pored over every rule, every regulation, every change, every process. He knew the history of the issues involved, and their legislative context. And he worked out how those changes were going to affect our clients years down the line.

That's because Austin understands more than the intricacies of his chosen field; he's studied the cultural, political and international forces that undergird the immigration landscape. He's a bit of a renaissance man. At Fragomen, we joke that our worldwide knowledge database is modeled on Austin's brain.

In addition to reshaping immigration law, Austin has introduced innovations to the legal industry that are common practice today. Again, his ability to listen is fundamental: He was one of the first to offer alternative fee arrangements, inspired by client requests for transparency and predictability in billing. He introduced the concept of level-to-level communications; a consummate communicator, he understood that clients prefer speaking with their counterparts at our firm, rather than only communicating with the most senior lawyer on the account. And Austin's famous talks during our 13th-floor lunches at Fragomen's old 515 Madison Avenue office inspired our client alert memos, a service now ubiquitous in the industry.

Any one of these innovations would mark a distinguished achievement for a lawyer after decades of practice; as would building a small U.S. immigration practice into a global enterprise with more than 50 offices worldwide. A lawyer of his accomplishment might be presumed to be aloof or even imperious. But Austin is the definition of a gentleman: He has an easy familiarity with every Fragomen lawyer and staff member he works with. He listens and empathizes. He learns about them and matches their strengths to the Firm's needs, thereby retaining top talent that best supports the evolving business of immigration law practice. Furthermore, he ensures that there are no barriers to their success besides the limits of their ambition and dedication. I'm reminded of the Spanish author Miguel de Cervantes, who said "fair and softly goes far." With such a management style it is no surprise that under his leadership, Fragomen has been celebrated for its unparalleled diversity.

I'll close on a personal note. Austin has been my mentor for years now; I've learned volumes from him. But more than any specific professional wisdom, I am grateful for his encouragement: He pushes me toward challenges for which I think I am unprepared, but for which he knows I am ready. And since I have unshakeable confidence in his judgment, when he trusts me, I trust myself.

I know that this is a confidence and an appreciation shared by everyone at Fragomen.

Carmita Alonso is a partner at Fragomen, Del Rey, Bernsen & Loewy.