There are many job opportunities both in the U.S. and abroad for teachers of English as a Second Language. Many teachers prefer teaching adult students, which often means teaching ESL classes with a particular focus, such as Conversational English or Business English. The specific qualification rules for degrees and certificates that you must have will vary depending on the country and school that employs you, but there are a few standard requirements for anyone to become an ESL teacher for adults.

Decide where you want to teach ESL. There are ESL classes and courses for adults available at colleges and private schools in the U.S.; however, they are generally easier to find in a city with a large ethnic population where demand is high. Most other countries, including those in Central and South America, Europe, Africa and Asia, have a high demand for ESL teachers who specialize in teaching adults. Take the cost of living of the city you choose into consideration.

Research the basics of teaching ESL to adults in the city you choose by joining a forum, such as ESL Teacher's Board or Dave's ESL Cafe, where you can interact with other teachers and ask questions both about the local schools and what to expect in the area.

Consider working with an employment agency, such as Footprints Recruiting, if you are going to teach ESL overseas. You can browse job ads and schools in your city of choice, but there are usually hundreds of positions and getting your questions answered is often difficult when the school receptionist or director isn't fluent in English. In addition, ESL classes for adults are often held at small private schools with minimal online presence, making them difficult to find and contact.

Find out the teaching requirements at a few of the schools in the area. In nearly every case you will need a minimum of a bachelor's degree. Some schools require the degree be in a related field, such as English, applied linguistics, language or education, while others will accept a degree in any field. Some schools both in the U.S. and abroad require certification, which is often considered a bonus with other jobs and may increase your salary. The best certificate for ESL teachers of adults is the CELTA (Certificate in English Language Teaching to Adults), which is available as an online course and is internationally recognized.

Read any contract you receive carefully, and have several others read it before signing. While contracts in the U.S. are usually standard, teaching contracts at private schools (which is the case with most ESL courses for adults) are often intentionally vague in wording.