According to Martin Yate, author of the "Knock Em Dead" books, resumes win interviews but references win job offers.  The higher the level of the position for which you are interviewing, the more thoroughly your references will be checked.

You must be certain that your references will seal the deal, not eliminate your opportunity.  Most people spend too little time focusing on their references while busy writing résumés, developing interview skills, networking, and deciding on the appropriate clothing for the interview.  All of these things are very important but your references are equally important.  In the days just before you receive an offer your biggest concern should be the quality of your references.

Few candidates realize that a primary reason they don't receive a job offer is because their references failed them.  Human resource professional report that about half of all checked references fall into the mediocre to poor category.

Some of the comments human resource professionals have recently heard when checking references include:

• "Company policy prohibits us saying anything.  We can only verify dates of employment and title"
• "All I can suggest is that you check his references very carefully."
• "Are you certain she gave my name as a reference?"
• "We miss him very much.  Too bad he was let go."
• "After we settle our lawsuit..."
• "Is she still in this field?"

References won't call to warn you that they won't be complimentary.  With companies policies changing, employee turnover running high in many HR departments, and new laws being enforced concerning references and company liability, it is safe to say that the reference situation is changing.

One way to gain greater control of your job search is to find out what potential references will say about you.  If the odds hold true, your references will range from outstanding to damaging.  When you know what former employers and co-workers will say about you, you can give only the names of your best references with greater confidence.  

After you select your references, be sure that your contact information is correct and list name, title, company, address, city, state, zip, telephone number, and e-mail address for each one. Make sure that your list is accurate and complete.  Print your references on letterhead that matches your resume and cover letter.  This makes a professional-looking presentation.  

• Try to meet with each reference personally.  If you cannot have a personal meeting, call and speak with each one. 
• Provide a copy of your current résumé to enable your references to see how you are marketing yourself to prospective employers. 
• Tell them the types of positions you are seeking and the qualities the companies require for the positions.  Make it clear that their references are critical to your selection for the job.

Reference checkers will usually ask your references to rate your skills in the following areas:

• Oral Communication
• Written Communication
• Decision Making
• Interpersonal Skills
• Crisis Management
• Financial Skills
• Leadership 
• Overall Performance
• Short-Term Planning
• Long-Term Planning
• Productivity
• Managerial Skills
• Employee Relations
• Personal Integrity 
• Technical Skills

Reference checkers will also ask references if they would enthusiastically recommend you, their thoughts on the circumstances of your separation from your previous jobs, and for any additional comments.

In-depth reference checks provide prospective employers with large amounts of information that can be used to break a tie between competing candidates. 

To help your cause, refresh the memories of your references regarding the position you held.  Review your past responsibilities and achievements for the company.  Then discuss your strengths and weaknesses.  

During your conversation, update them on what you are doing, how you have added experience and turned old weaknesses into strengths.  If they believe that you are aware of your weaknesses, it may prompt them to tell interviewers that you are open-minded and striving to grow professionally.