The OECD Washington Center regularly recruits for undergraduate interns.
Of interest to those interested in issues related to career guidance: Career Guidance: a Handbook for Policy Makers
Learning for Jobs
OECD looks to employ researchers with a variety of educational and national backgrounds. Details are available online.
Use this link to enter the site for OECD reports, annual statistical compilations, ebooks, and data. (UCSD-affiliated users only)