American Dental Partners was founded in 1995 to be the leading business partner to dental group practices in the nation. Our sole commitment and focus is to bring value to dental group practice. Over the years we have affiliated with some of the largest and most respected dental group practices in the country. Today we are affiliated with 20 dental groups which have 200 dental facilities in 18 states.

There are many ways in which we add value to dental groups, but none is more important than helping them buildenduring organizations. This is not an easy concept to articulate, nor an easy one to execute. Especially in a business like dentistry which is so highly fragmented. It is nearly impossible to measure the difference between good and great in an industry where tens of thousands of small businesses lack common measurements. However, for American Dental Partners and our affiliated dental group practices, we can measure against ourselves and then adopt a philosophy of "good is never good enough." There is always room for measurable improvement in an enduring organization.

Our goal, and that of our affiliated dental group practices, is to seek excellence in all that we do. We strive to achieve high levels of patient satisfaction, to create professional practice environments, to maintain first class dental facilities, to pursue continuous training and education, to invest in the future of dentistry through community giving and, above all else, to create an organization that will endure through successive generations. They say all good things come to an end, but we say great things should never end. They should get better and stronger as time goes by.

We have learned over the years that much of what commonly takes place in many dental practices is done for the here and now, without much structure and process - not surprising in such a fragmented profession, but not for a professional health care organization with multiple locations and numerous professionals providing care to many patients. We believe structure and process are necessary for dental group practices to strive for excellence and achieve greatness. Excellence can mean many things, but with patient care it must mean consistency and predictability in outcomes.

Over the years we have found that not only is it rare to find an enduring organization in the dental profession, we have found that it is rare to find the resources required to be successful in building an enduring organization. More than any other accomplishment we have made since our founding is that we have developed many of these resources and with each passing year, our resources expand and our experience broadens.

Today we have vast resources that we deploy to enhance the growth and success of our affiliated dental group practices and we make substantial ongoing capital investments to support each affiliate's growth. We assist with organizational planning and development, recruiting, retention and training programs, quality assurance initiatives, facilities development and management, employee benefits administration, procurement, information systems, marketing and payor relations, and financial planning, reporting and analysis.

When we think of mission at American Dental Partners, we think of the word purpose. A company's purpose is its reason for being. Purpose goes to the inner soul of an organization and as such it never changes. An organization can pursue its purpose but it will never achieve it. Purpose is not an objective or "to do list" item that one crosses off.

core purpose is to be the leading business partner to group dental practices in the nation. We work very hard towards this goal. But as we do, we raise the bar to even greater heights. As we close in on them, we raise the bar again ... and it goes on and on.

Purpose, though, is only one component of an organization's core ideology. The other very important component is core values. Core values define who you are and what you stand for. Core values actually exist in all organizations whether or not they are clearly defined and articulated. We articulated our core values in 1995, and they have remained unchanged ever since.

Core Values
We believe in five core values which provide the foundation on which American Dental Partners is built. These values represent the way we intend to do business, and we endeavor to uphold them at all times.

Ethical
A promise to conduct business in an honest, fair manner and with the utmost integrity.

Relationship
Put people first. A commitment to treat all people with respect and human decency.

Social Responsibility
A commitment to act in a responsible manner with total regard for our families, communities and environment.

Fiscal Responsibility
An obligation to act in a financially prudent manner for the benefit of our patients, shareholders, affiliates and employees.

Excellence
In all that we do, commitment to achieving the best results.

American Dental Professional Services (ADPS) is a third party administrator dedicated solely to the dental market. ADPS also has its own family of dental plans and has contracted with dentists across the country to form a dental network. ADPS is committed to providing a dental health care network that brings together patients and dental care providers in a variety of ways.

American Dental Partners Announces AAAHC Accreditations
Wakefield, MA - May 3, 2007 - American Dental Partners, Inc. (NASDAQ:ADPI) announced Associated Dental Care Providers (Arizona), Forward Dental (Wisconsin), Longhorn Dental Associates (Texas), Orthodontic Care Specialists (Minnesota) and Western New York Dental Group (New York) have been re-accredited by the Accreditation Association for Ambulatory Health Care ("AAAHC").

American Dental Partners encourages its affiliated practices to pursue AAAHC accreditation as a means to set and maintain measurable quality benchmarks and achieve the highest possible standard of patient care. Dr. Jesley C. Ruff, Senior Vice President and Chief Professional Officer of American Dental Partners, works with the Company's affiliated practices in the pursuit of accreditation. "We hope that by having our affiliated dental groups be part of a select group of dental practices accredited by the AAAHC, American Dental Partners will be at the forefront of promoting clinical excellence in the dental profession," said Dr. Ruff. "While AAAHC accreditation is a rigorous and demanding process, we believe it will help our affiliated dental group practices continue to recruit high quality professionals and enhance relationships with patients and local dental communities," Dr. Ruff added.

The AAAHC is a peer-based, not-for-profit organization that is nationally recognized for conducting extensive evaluations of ambulatory health care organizations to ensure the highest quality standards. More than 2,700 ambulatory health care organizations across the United States are accredited by the AAAHC.

American Dental Partners is one of the nation’s leading business partners to dental group practices. The Company is affiliated with 22 dental groups which have 213 dental facilities with approximately 1,958 operatories located in 18 states.

"Safe Harbor" Statement under the Private Securities Litigation Reform Act of 1995: With the exception of the historical information contained in this news release, the matters described herein contain "forward-looking" statements that involve risk and uncertainties that may individually or collectively impact the matters herein described, including but not limited to the possibility that we may not realize the benefits expected from our acquisition and affiliation strategy, economic, regulatory and/or other factors outside the control of the Company, which are detailed from time to time in the "Risk Factors" section of the Company's SEC reports, including the annual report on Form 10-K for the year ended December 31, 2006.