Lieutenant Selar was a Vulcan doctor on the USS Enterprise-D in the 2360s into the 2370s.
In 2365, Selar was part of an away team which responded to a distress call from Gravesworld. Selar was sent instead of Dr. Katherine Pulaski because the Enterprise needed to rescue the damaged transport vessel USS Constantinople several light years away. She examined Dr. Ira Graves, despite his protests, and diagnosed him with Darnay's disease. Selar was later called to the captain's ready room by Captain Picard to discuss what had happened on Gravesworld and possibly shed some light on Lieutenant Commander Data's unusual behavior.
Dr. Beverly Crusher assigned Selar to sickbay ward three in mid 2369. Selar was to treat ambulatory cases resulting from a Lenarian assault on a conference attended by the Enterprise.
Selar was not Guinan's usual doctor. Selar was on duty in sickbay in late 2369 when Dr. Crusher was relieved of duty after she performed an autopsy on Dr. Reyga against the policies of the Ferengi death ritual. After Guinan came to Crusher complaining of tennis elbow, Crusher suggested she go see Selar. Guinan refused, claiming she was very particular about her doctors.
In 2370, Crusher had Selar run a biospectral analysis on the body of Ned Quint after he was killed by Ronin.
Dr. Crusher wanted to consult Selar and Dr. Hacopian in mid 2370 after it appeared as if the entire Enterprise crew was affected by a virus. Before they could arrive in sickbay, Crusher was nearly paralyzed by venom after being attacked by Worf. The infection was later determined to be the first case of Barclay's Protomorphosis Syndrome.