Spondylitis Association of America (SAA).
The spondylitis association of America is a non-profit organization. Is the first and remains the largest resource for people affected by spondylitis. Through their efforts, they have helped advance education, research and treatment for ankylosing spondylitis (AS) and related diseases.

National Ankylosing Spondylitis Society (NASS), UK.
The NASS is a non-profit organization and contains a large volume of information about ankylosing spondylitis. They publish a very good Guide Book on AS.

Ankylosing Spondylitis International Federation (ASIF).
World-wide organization of national self-help societies of patients suffering from ankylosing spondylitis or related diseases

MedlinePlus information on Ankylosing Spondylitis.
A very useful site by the National Institutes of Health on all aspects of ankylosing spondylitis including diagnosis, treatment, disease management, clinical trials, alternate therapy and much more.

Mayo Clinic.com information on Ankylosing Spondylitis
Comprehensive source of information on all aspects of ankylosing spondylitis and drug treatments

WebMD information on Ankylosing Spondylitis
Comprehensive source of information on all aspects of ankylosing spondylitis and drug treatments

MedicineNet.Com
Comprehensive source of information on all aspects of ankylosing spondylitis and drug treatments

Arthritis Foundation of America
Comprehensive source of information on all arthritis related diseases.

RxList.com
RxList is an online medical resource dedicated to offering detailed and current pharmaceutical information on all brand and generic drugs.

Clinical Trials relating to Ankylosing Spondylitis
A service of the National Institutes of Health that lists availability of clinical trials relating to ankylosing spondylitis.

Clinical Trials relating to AS and arthritis
A service of CenterWatch, a publishing and information services company that lists availability of clinical trials relating to ankylosing spondylitis and arthritis related diseases.