p.m.terrell’s life, like the novels she writes, took a series of different twists and turns. Until 2000, her writing took a back seat to earning a living. Through a stroke of luck (or some would say, fate) she was working for a subsidiary of IBM when the first Apple computers rolled off the production lines, and she found herself on the ground floor of a mushrooming industry.

In 1984, p.m.terrell, known then as Trish McClelland, opened her first business, McClelland Enterprises, Inc. It was one of the first companies in the Washington, DC metropolitan area that was devoted entirely to personal computer classroom instruction. She personally wrote all of the course manuals that were used in the classes. During this period, three of her computer how-to books were also published: Creating the Perfect Database, published by Scott-Foresman, followed by The Dynamics of WordPerfect and The Dynamics of Reflex, both published by Dow Jones-Irwin. She also wrote a series of columns for The Washington Business Advisor, The Washington Post, and The Washington Business Journal, among others.

Ten years later, she became Patricia McClelland Terrell, and opened her second business, Terrell Computer Services, Inc., which is now known as Continental Software Development Corporation, U.S.A... In 1996, the business was relocated to Chesterfield, Virginia.

Her clients in these two companies included the CIA, the United States Secret Service and the Department of Defense. She also worked with local law enforcement agencies. She developed a specialty in computer intelligence and computer crimes.

She began writing full-time in 2000 and with the success of her books, she largely retired from the computer industry in 2002, keeping only non-profit clients with whom  she had a personal interest.