Tired of brokers checking you out? It's time to check out your broker.

This week, the National Association of Securities Dealers launched an updated version of NASD BrokerCheck, an online service that provides information about the conduct of securities firms and a broker's professional background. According to the NASD, more than 4.7 million searches were conducted on the system last year. That's a lot of queries, and time well spent before choosing an investment professional.

Introduced online in 1998, the database contains information on about 5,100 active securities firms, 660,000 registered brokers, and many inactive firms and formerly registered brokers. The collected data includes employment history, licensure and qualifications, criminal and investment-related misdemeanor records, disciplinary actions, consumer-initiated complaints, arbitration and bankruptcy proceedings, and end of employment involving allegations of misconduct or failure to supervise. Any specific disclosures are put into the relevant context when evaluating a particular individual or firm.

The more user-friendly and faster version of the system is now available 24 hours a day, seven days a week, so there's no excuse for not finding time to do your homework before selecting a broker. Before you invest your money, invest a bit of time in getting to know your financial partner.

For suggestions on which broker can give you the best service to meet your investing needs, take a look at the Fool's Broker Center. You'll find helpful comparisons among top discount brokers as well as useful criteria to evaluate prospects.

Fool contributor S.J. Caplan is a former vice president and assistant general counsel of Goldman Sachs and a former vice president and derivatives finance specialist at Lehman Brothers. She serves as an arbitrator for the New York Stock Exchange and the NASD.