When it comes to mechanical aspects of writing, few details seem to trip writers up as much as capitalization: when to use uppercase letters, and when to use lowercase letters.
Specific job titles preceding a person’s name are capitalized, but descriptions are not. For example, “Marketing Director John Doe” is correct, but “Marketing Chief John Doe” is not, unless “marketing chief” is John Doe’s actual title. After a name, titles are lowercase regardless of whether they are specific or general: “John Doe, marketing director at ABC Industries.”
If you modify even a specific job title, such as noting that someone no longer holds a position, what appears to be specific becomes an apposition, part of a job description rather than a title: “former marketing director John Doe.”
Some style guides disregard this last rule, and some publications choose to capitalize “president” when referring to the head of state even when the word appears in isolation from the title holder’s name, but this is an unnecessary nicety. Likewise, ordinary job titles in isolation are never capitalized. For example, the job title in “The park ranger asked for our permit” is a mere description, and needs no emphasis.
Job titles are at times absurdly attenuated, and placing them before a person’s name can wear readers out. Confronted with a magnificent moniker like “Oracle Principal Product Manager for Windows Technologies John Doe,” relax the identification a bit: “John Doe, Oracle’s principal product manager for Windows technologies” (the proper name Windows remains capitalized even after the name), is a gentler approach.
Capitalization of job titles and general descriptions alike is permitted in direct address — when you are writing to someone (or transcribing a speech directed at them) and using the title or description in place of a name: “That’s an order, Sergeant”; “I’ll get right on it, Chief.”
Capitalize formal and informal family-relationship labels, too, as in “If only Father were here” and “I’ll tell Mom!” but not in “Wait until your father gets home!” or “I saw your mom yesterday.” Terms of endearment aren’t capitalized, either: “I’ll get it, dear.”
Most terms of respect are capitalized (“I object, Your Honor”), but “sir” or “ma’am”/”miss” are not (unless you are addressing a letter or an email, in which case you should write “Dear Sir” or the equivalent).
The take-away about titles: Capitalization is seldom called for. Unless you’re using a person’s exact job title, and only the job title, immediately before that person’s name, chances are you shouldn’t capitalize it.