Endometriosis is a common problem affecting millions of reproductive age women worldwide. It is frequently associated with pain, and it is the number one cause of infertility in women over the age of 25. As a radiologist, one must be familiar with the various presentations of endometriosis to accurately diagnose and help triage patients. Although ultrasound remains the mainstay of diagnosis, magnetic resonance imaging (MRI) is frequently used in a complementary fashion as a problem-solving tool. This article will expand upon the complementary role of MRI and highlight clinical scenarios where MRI can provide additional information that could not be obtained in the patient's initial ultrasound.