What qualifications do you need to be an investment banker or stock broker?

What does it need to be "in"? i.e. does it need to be in Business, Investing, banking etc etc

Investment banker and stock broker are two completely different things.

To be an investment banker you need a four year degree in a field such as finance, accounting, math, statistics etc . The better school you go to the better bank you have a chance of working for.

To be a stock broker you need a GED and the ability to sell. You also need a National Association of Securities Dealers Series 7 license. Its not that difficult. The Bar exam it aint. You also need to be sponsored by a broker for that. Its the same as being a real estate agent or insurance salesman; certification and the ability to sell sell sell. Stock brokers have no fiduciary responsibility. They have no responsibility to act in a clients best interest. All they have to do is act in a legal and somewhat ethical manner. Commissions are what its all about. Salesmanship is job 1.

You need a bachelors degree from a good school at the bare minimum. Pretty much, you need an MBA from a top B school to have the best shot. Best shot would be a bachelors in econ, business, accounting or math. MBA from harvard, columbia, wharton, kellogg etc. If you have good grades at a good college for your undergrad, you can still get a analyst position at a good bank and work your way up. but get a good MBA and work hard for your best shot

MBA (Ivy League)

Jeff410 is mostly right on in his answer...
I work in the industry...
Investment Banker and Stock Broker are entirely different.

Investment Bankers are recruited from Ivy League schools... Harvard, Stanford etc... if you're not from a top 10 business school your application might as well say community college.
There are back doors though.. you can be hired in support positions.. a few years of 90 hour work weeks with favorable opinions from superiors and get promoted... if you're young, have no other responsibilites and are so motivated its a possibility.

Stock Brokers .. though technically there's no requirement other than sponsorship by a brokerage firm and passing some exams... (some say they're easy but the series 7 has about a 35% fail rate) you'll need to be Insurance licensed, and commonly pass the 7, 52, 63, 6, 65 exams... I have known a few with no more than a GED and good sale skills.... however .. if you cannot talk intelligently about investing, finance, international business, taxes, inheritance law and protection of assets and the economy in general... most clients will see right thru you... and the advice you give will suffer... Not all successful brokers have stellar pedigrees... and some terrible brokers do... however all successful ones seem to be personable.. good at sales.. with a sharp mind, quick wit, with an interest and aptitude towards economics and finance..... and most of all ambitious.. they have to be able to meet someone, gain trust, ask intimate questions.. and solve for problems....
if the broker fails to do that... and doesnt know what he's doing due to ignorance or lack of education.. he will lose clients and fall out of the industry.

anyways... sorry for the long answer.

get bonded.the higher the bigger the accounts./good ref.