WARREN, N.J.--Chubb Corp. Chairman and Chief Executive Officer Dean O'Hare will retire within a year, the insurer announced Tuesday in reporting gains in its results for the first quarter.

Mr. O'Hare, a 39-year Chubb employee and its CEO for the last 14 years, said the insurer's board would begin searching for a successor immediately. "I will remain as long as needed to help effect a smooth transition," he said in a statement.

"I'm turning 60 in June, and I'd like to retire while I'm still healthy and young enough to enjoy it," Mr. O'Hare said.

Warren, N.J.-based Chubb has outperformed many other property/casualty insurers during Mr. O'Hare's tenure as CEO, averaging a 15% annual compounded return on equity, Chubb Director Joel J. Cohen noted. The insurer has also faced its share of setbacks: Recently, these included surety bonds Chubb wrote to cover now-defunct Enron Corp.'s performance in a series of oil and gas deals, an episode Mr. O'Hare had lambasted as a "gross embarrassment" for the insurer.

Nevertheless, he said "it will be gratifying to leave at a time when Chubb's global network is in excellent shape as we begin to reap the benefits of the turnaround and a favorable insurance market environment."

That favorable environment contributed to improvements in Chubb's first-quarter results. Net premium volume jumped 26.4% to $2.19 billion from a year earlier, while net income rose 13.3% to $198.2 million.

Rising insurance rates accounted for much of the increased volume, Chubb reported. Commercial insurance, Chubb's largest business segment, recorded a 34.6% gain in net premiums to $892.9 million in the first quarter--mainly from higher prices--while the segment's combined ratio fell to 95.7% from 106.6% in last year's first quarter.

Specialty insurance, Chubb's second-largest segment, saw a 24.1% rise in volume to $795.5 million, but rising directors and officers liability losses produced a combined ratio of 95.4% for the quarter, up from 92.6% for the same period last year.