Environmental impact assessments (EIA’s) are an important part of environmental
regulations. However, they differ in what projects are covered, what aspects they need to include, the
amount of public involvement, etc. Studying these differences can be very instructive. As examples
of these differences, this paper compares EIA’s in Thailand and the USA. Both countries’s assessments
have the strong and weak points, and we can learn from both. The US law only covers public
projects, a small percentage of the total. Thailand uses a listing method which is only as good as
the list is. The most important lessons are that alternatives and scoping must be made and should
begin early in the process, and that the public must be involved in the process. In all countries, there
is a desire to avoid the EIA procedure; therefore enforcement of the laws and regulations is a must.
Conflict resolution methods can also be incorporated.