orthodox
Meaning: conventional, conforming to established protocol
Usage: The company’s profits dwindled because the management pursued orthodox business policies that were incompatible with new industrial trends.
punctilious
Meaning: eager to follow rules or conventions
Usage: Punctilious Bobby, hall monitor extraordinaire, insisted that his peers follow the rules.
conformist
Meaning: one who behaves the same as others
Usage: Julian was such a conformist that he had to wait and see if his friends would do something before he would commit.