Abstract: The present invention provides antigenic proteins of Chlamydia trachomatis. The proteins of the present invention are useful for eliciting an immune response to Chlamydia in a patient. For example, an effective amount of protein of the present invention or fraction thereof may be administered to a patient for eliciting a Chlamydia specific immune response. In another example, a method of raising an antibody specific for Chlamydia trachomatis elementary bodies (EB) is provided in which a protein of the present invention is administered to a patient.