Star Trek "Dress Uniform" Engineering Dept.      Engineering/operations uniforms are worn by anyone who is involved in the maintanence of the ship, or any section which isn't command or the sciences. The Engineering/operations uniforms are a bright red shirt. Dress uniforms were often used in officer hearings/courtmartial hearings. They were also often seen in diplomatic occassions.
The Original Series was the first series of Star Trek, and as such, is the template for all later versions. While the 2nd-6th movies appeared to not have a seperate dress uniform, the duty uniform seemed to take after the original series' dress uniform.
Uniforms: Star Trek Uniforms: Dress, Command