While interviews are generally not required for applicants of certain ages outlined above, consular officers have the discretion to require an interview of any applicant, regardless of age.

If you are age:	Than an interview is:
13 and younger	Generally not required
14-79	Required (some exceptions for renewals)
80 and older	Generally not required

You must schedule an appointment for your visa interview, generally, at the U.S. embassy or consulate in the country where you live. You may schedule your interview at any U.S. embassy or consulate, but be aware that it may be difficult to qualify for a visa outside of your place of permanent residence.

Wait times for interview appointments vary by location, season, and visa category, so you should apply for your visa early.