The business of following up after a job interview should begin before you leave the interview, by asking the company when they expect to make a hiring decision. This gives you a time-frame for further follow-ups. After each interview, you should send a note within 24-48 hours, while things are still fresh in your mind. How you follow up is as critical as following up in the first place.
Address a tailored note, usually an e-mail, to the person or people you met. Spell everyone's name correctly, including the company name. Errors here can be a game-changing embarrassment. Start by thanking them for the opportunity to meet and acknowledge that they took time out of their day to do so.
Next, express enthusiasm for the role and outline why you think you would be a good fit - you should focus on what the hiring manager is looking for. Something along these lines: "I listened, I understand your needs and your challenges, and here's how I can help you address those." In your conclusion, highlight the fact that you remain interested in the position and outline that you will follow up with them within the specified time frame.
Lastly, thank them again. Keep things relatively brief and to the point - anything requiring the reader to scroll down the page is too lengthy. If you are using a recruiter, they should do most of this on your behalf and follow up in the time frame agreed. Even so, it is still worth sending a note - just copy in the recruiter so they are kept in the communication loop. Push a recruiter to get you feedback on the interview and update you on the time frame regularly.
Walter Ellicott, managing director, Ellicott Long Limited, recruiting professionals for the property and construction industries in Asia