Constance Said:

What are the best careers for an INTJ personality type who is interested in research?

We Answered:

Something scientific not involving people, like Physics, Chemistry or Finance.

Enrique Said:

What are the best careers for an ISTJ personality type?

We Answered:

Various websites will list these things for you.

Typically, an ISTJ does well in an environment:

- that is "stable"

- where there aren't many surprises

- where the work is consistent, reliable, and predictable

- where they have enough space and time to think carefully through all the details

- where they aren't expected to "emote" too much but can focus on logic

- where people are trustworthy/reliable and act accordingly to what is expected of them.

- where there is some structure and also very clear levels of authority (so everyone knows what their roles and responsibilities are, and it's clear who is in charge)

ISTJs thus do pretty well in "thinking-based" impersonal jobs, such as engineering, accounting, some low-level management (depending on the ISTJ), scientific work involving care and diligence and methodical processes.

They are also good at pointing out practical problems that someone might face, based on the ISTJ's knowledge and experience.

Dave Kelly's Ptypes site has a list of jobs that could fit an ISTJ type:

management
accounting
auditing
efficiency expert
engineer
geologist
bank examiners
organization development
electricians
dentists
pharmacist
school principals
school bus drivers
file clerk
stock broker
legal secretary
computer operator
computer programmer
technical writer
chief information officer
police officer
real estate agent