Jake Adams runs his own security agency.
This business is a mixture of detective and bodyguard work. With considerable contacts around the world, he is often called upon for odd, confidential work and his reputation is backed by a good deal of success. He remains friendly with the American military and with the Intelligence community and often does work for them.
Adams worked for several years in Air Force Intelligence where his area of expertise was chemical and biological weaponry. After becoming proficient in Russian while with them, learning more about the Ukraine than he ever wanted. He also became an expert in counter-terrorism, especially as it might use such weapons. It was this knowledge that made the CIA make him an offer too appealing to turn down. He switched to the Agency and begane a period of several years in which he was an agent who traveled extensively about Europe.
Eventually the routine of just following orders from above without real input got to him and he decided he needed another break. It was the work he did for the Air Force and the Agency that brought him to the attention of numerous corporation heads who tried to get him to work for them upon leaving the CIA. When he finally decided to go to the private sector, however, it was on his own terms. He chose to start his own company. He now takes their jobs but he does things his way and for a very good rate of pay.
Adams moved back to the States, Portland to be exact, and located his company there. He has been on his own for about three years at the start of the series.