Consultant
A consultant was an individual, who advised a person or an institution as an expert in a specific field.

Private investigators sometimes worked as consulting investigators assisting the police. William T. Riker called Sherlock Holmes "history's greatest consulting detective" in 2364. ()

Shannon O'Donnel worked as a consultant engineer on the Millennium Gate in the early 21st century. ()

In 2370, Rom suggested himself to become Quark's consultant in negotiations with the Dosi. Quark agreed he needed help, but chose  instead of his brother. ()

In 2374, Morica Bilby was employed by the Tigan family as a favor to the Orion Syndicate, paid as a shipping consultant but without any actual work done, in order to provide for her and her children. ()

In 2375, Medical Consultant Program Beta one featuring a holographic Crell Moset was created to serve as a consultant for The Doctor. ()

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Occupations