After graduating from Cornell Law School in 1989, Eisler joined the CIA, where he held a covert position with the Directorate of Operations. He left the Agency in 1992 and thereafter worked as a technology lawyer and startup executive in Silicon Valley and Japan, earning his black belt at the Kodokan International Judo Center along the way. He started writing full time in 2002 when he sold the rights to his debut novel, Rain Fall, the first of his six-book series featuring John Rain.

Eisler's bestselling thrillers have won the Barry Award and the Gumshoe Award for "Best Thriller of the Year," have been included in numerous "Best Of" lists, and have been translated into nearly twenty languages. In April 2009, Sony Pictures Japan released a mostly Japanese language film version of Rain Fall starring Shiina Kippei as Rain and Gary Oldman as Rain's nemesis, CIA Station Chief William Holtzer.

Eisler lives in the San Francisco Bay Area and Tokyo.