The New Yorker once published a cartoon showing a Roman nobleman being fanned by a slave. The caption reads, "The word 'slave' is so degrading. Why don't we call you 'intern.'"
Although interns do tend to be low on the organizational totem pole, few spend their days feeding grapes to their advisers. It's worth putting up with a little hardship because, for students considering careers in science, summer internships are great opportunities to learn how research is done, get to know peers and potential mentors, and maybe even do some real science. It's probably the best way to decide whether a career in scientific research interests you.
So how do you go about finding an internship? If you want one on your campus or close to home, faculty members are probably the best information sources. Your department or institution may maintain a centralized listing of all the campus's summer research opportunities. If they don't, just walk around the building and talk to professors.
If you are ready, willing, and able to go elsewhere for the summer, this page, which lists internship opportunities in the United States and Europe, may provide some help. Listed below for U.S. readers is a sampling of internship opportunities from Science Careers' GrantsNet  site, as well as other sources in the public and private sectors. Most of the opportunities for U.S. students are in the United States, but there are a few links to internships in Europe for Americans on this list as well. If you are in the United States on a student visa, check with your campus foreign-student adviser to find out if your visa allows you to be employed as an intern. Most--and perhaps all--of these opportunities provide or will help you find affordable housing.
We're not sure whether internship opportunities in Europe are more rare or if they're just harder to find. The Engineering and Physical Sciences Research Council in the United Kingdom offers some Vacation Bursaries  that are comparable to the U.S. National Science Foundation's Research Experiences for Undergraduates (REU) program , which offers research opportunities at host institutions across the United States--and beyond. Such examples are not the norm in Europe, but still, we managed to find quite a few internship opportunities for European undergraduates .
At the end of this page are links to more internship resources, including GrantsNet's current Funding News and main search engine for student opportunities. Happy hunting!
By the way, we know about a few summer internship programs that have very early deadlines. The internship program for the U.S. Central Intelligence Agency , for example, has a 1 November deadline, so it's too late to become a 2009 Summer Spook, but there's always next year.
If you have, or know of, a summer internship program for undergraduate science students, and it isn't listed here, please send us e-mail  and we'll add it to the list.
AAAS/Entry Point: Internships for Students With Disabilities 
Alliance for Graduate Education and the Professoriate: Summer Research for Undergraduates 
American Chemical Society: International Research Experiences for Undergraduates  (IREU) program
Army Educational Outreach Program: Gains in the Education of Mathematics and Science 
CDS International: Internships abroad  in a variety of fields in Argentina, Germany, and Spain
Cold Spring Harbor Laboratory: Summer Undergraduate Research Program 
Department of Energy: Science Undergraduate Laboratory Internships 
German Academic Exchange Service: Research Internships in Science and Engineering 
Howard Hughes Medical Institute: Janelia Undergraduate Scholars 
Incorporated Research Institutions for Seismology (IRIS): IRIS Internship Program 
Integrative Graduate Education and Research Traineeship: Summer Research for Undergraduates 
Massachusetts Institute of Technology: MIT Summer Research Program 
National Aeronautics and Space Administration: Undergraduate Student Research Program 
National Cancer Institute: Integrative Cancer Biology Program, Summer Fellowships 
National Institutes of Health: Summer Internship Program in Biomedical Research 
National Oceanic and Atmospheric Administration, Environmental Protection Agency, and National Center for Atmospheric Research: Significant Opportunities in Atmospheric Research and Science 
Pasteur Foundation: Paul W. Zuccaire Undergraduate Summer Internships  in Paris, France
Pfizer: Summer Internships 
Samuel Roberts Noble Foundation: Undergraduate Internships 
United Negro College Fund-Merck: Undergraduate Science Research Scholarship Awards 
Biochemical Society: Summer Vacation Studentships  in the United Kingdom
European Commission: Erasmus actions - Student Mobility for Placements  (seek information on how to apply at your host institution)
The European Molecular Biology Organization allows you to search for internship funding on its EMBO Life Sciences Mobility Portal .
European Organization for Nuclear Research (CERN): 2009 Summer Student Programme 
Europlacement  search engine
Engineering and Physical Sciences Research Council: Vacation Bursaries  in the United Kingdom
Federation of European Biochemical Societies: FEBS Summer Fellowships 
La Fondation Pierre Ledoux - Jeunesse Internationale: Bursaries  for internships done in a medical research laboratory belonging to the International Network of Pasteur Institutes
Nuffield Foundation: Nuffield Science Bursaries Undergraduate Research  in the United Kingdom
Spanish National Centre for Cardiovascular Research (CNIC): The Cicerone Program  in Madrid, Spain
Universia-Becas : information and grants search engine for Spanish-speakers
Wellcome Trust: Vacation Scholarships  in the United Kingdom
Association for Computing Machinery: Computer science and information technology  internships
Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland: International Summer Research Program . School of Life Sciences
The European Molecular Biology Organization: Search for internship funding on its EMBO Life Sciences Mobility Portal 
FAROGLOBAL : an international industry internship program for students in Spanish universities
Fonds de la recherche en santé du Québec (FRSQ): Summer Program for Students in Medicine and Health Sciences 
GrantsNet: Student support search page 
Current GrantsNet Funding News: Student support 
More opportunities from The International Association for the Exchange of Students for Technical Experience 
InternJobs.com : Search engine for internships across industries
Undergraduate internships with more U.S. government agencies and labs 
International Student Exchange Programs : A network of 275 colleges and universities in 39 countries
Updated: 3 February 2009
If you know of an undergraduate internship opportunity that's not listed here, please share it with us at firstname.lastname@example.org .