The Science, Technology, Engineering and Medicine Public Relations Association  (STEMPRA) is a membership organisation set up by PR people from not-for-profit science bodies (learned societies, funding bodies, etc) in the UK. The site includes a section on useful advice for science communicators.
Two networking organisations for PR people worldwide are the International Public Relations Association  and the Global Alliance for Public Relations and Communication Management .
The European Public Relations Confederation  (CERP) is the umbrella organisation of national and professional PR associations all over Europe. Contact details for PR associations in 22 European countries can be found through their Members page .
The Canadian Public Relations Society  (CPRS) is the professional network of PR specialists in Canada. CPRS and all its local member societies provide professional development for their members in the form of job recruitment registries and networking opportunities, an annual national conference, a directory of all members, and several other services and national certification.
The Institute of Public Relations  (IPR) is the professional body for UK public relations practitioners. The Careers  section of its Web site offers advice on finding work experience in PR. In addition, you'll find information about any forthcoming Careers Days--the career fair focussing on the PR industry that the institute organises. The IPR has sectoral groups  devoted to special interests within the PR field--including one for the motor industry and one for technology and engineering PR.
The PR Consultants Association  is the trade body for UK PR agencies and independent consultants. The site's Careers section  provides advice specific to working and finding a job in an agency.
Probably the most useful section of the Public Relations Society of America  Web site for those wanting to learn more about careers is the career development resources  page. Look in the 'reading room' for a guide to PR careers.
Syntec Relations Publiques  is the professional body for PR people in France. The sector is expanding there both in terms of number and diversity of jobs, and the (all-in-French) Web site offers an overview of PR careers and training.
The Institute of Public Relations of Singapore  is the regional professional organisation for public relations practitioners. It runs courses and networking events for students and members.
PR Canada  is an online newsletter about the Canadian PR scene. Available free by subscription, it covers Canadian industry news, career opportunities, media, and more, including an archive of hands-on how-to articles written by experienced practitioners.
Is PR Week  the Science of the PR industry? Hmmm, perhaps not, but you can access US, UK, German, Asia-Pacific, and Chinese editions from here to learn more about what PR people consider news. And, of course, those all-important job listings ...
The Canadian Public Relations Society provides a list  of educational institutions in Canada that provide programmes in PR.
The European Public Relations Education and Research Association  (EUPRERA) has produced a survey of current PR training across Europe. It's not immediately obvious how to use the survey Web site . However, run your mouse over the little pictures to discover which country each relates to--then click to get brief information about that country's educational system, what types of PR training are available, and what the curricula of the different programmes include.
The UK's Institute of Public Relations runs Diploma and Advanced Certificate courses . In addition, PR is one of the elements of the CAM Foundation's  Advanced Certificate course in marketing communications and can be studied part-time.