Mr. Bayer says his clients have been able to settle the details of their termination to their satisfaction and secure a positive reference from bosses who have fired them. Doing so allows both the employee and the employer to move on, he says. He suggests having a friend call under the guise of an employer to ensure that your former boss sticks to the agreed upon story.

When asking an ex-boss for a reference, pitch your assets. "Remind the employer of what you have accomplished, because they may just be thinking of the recent event that you were fired over and lose focus of the good qualities," says Linda Matias, president of CareerStrides, a career and outplacement- consulting firm in Melville, N.Y.

2. Ask a previous boss to be a reference.

When Leslie Macabeo, 33, of Westminster, Calif., resigned from her job as dean of academics at a Huntington Beach, Calif., college in April after severe criticism from her supervisors, she didn't feel comfortable asking them to be references.

As an alternative, she used the former president of the college as a reference, says Ms. Macabeo, who had been with the college for two years. She secured a new job within a week of the dismissal and is now director of development at the Creative Collection, an after-school arts program in Aliso Viejo, Calif.

If you haven't kept in touch with former managers, reopen the lines of communication. Update them on your situation and then ask for a reference.

3. Find an ally.

Chances are good some co-workers won't side with your boss and instead sympathize with your situation. It is important to ask these allies to be a reference immediately after you leave the company, while they are still friendly with you.

In 1999, Tom Pulley, now 56, was let go from a managerial position at an aerospace and defense company in Dallas after 25 years with the employer. Because of a strained relationship with his supervisor, Mr. Pulley decided not to ask him for a reference.

"It would not have been an acceptable reference," says Mr. Pulley. Instead, he sought out another supervisor at the company who understood his circumstances. Mr. Pulley, who now has a consulting firm in Dallas, says he still lists that supervisor as a reference in proposals to clients.

4. Seek out a client or vendor.

Be creative with your references by reaching further into your network to associates you brought to the company or vendors.

"People always think they have to use their bosses as references instead of considering a client they found who brought in $5 million each year," Ms. Matias says. These supporters may be able to provide a different perspective than employers.

5. Use the human-resources department.

If you must verify employment but are worried that your boss may say something negative about you, list a human-resources manager at your former employer.

In most cases, company policies limit human-resources professionals to releasing only your title, length of employment and salary. "Many companies have strict rules and won't divulge why an employee no longer works there," Ms. Matias says.