The UNAM counts with a kind of "ranks" which exists separately for lecturers (profesor), researchers (investigador) and technicians (técnico académico).
The lowest rank is Asociado A, the highest Titular C. Payment and the right to participate in commissions, councils etc. depends greatly on the level. Requirements to obtain a position as lecturer or researcher are (as I believe) somehow equivalent but lower for tecnicians. Requirements to be able to rise within the hierarchy vary from institute to institute.