Significance Fetal extravillous trophoblasts (EVT) invade uterine tissue and interact with maternal immune cells during pregnancy. EVT express human leukocyte antigen-C (HLA-C) and -G (HLA-G). Although polymorphic HLA-C can elicit a maternal immune response, HLA-G has been associated with induction of immune tolerance. We have succeeded in isolating all maternal immune cell types as well as EVT from human placental tissue. These methods were used to elucidate the unique charateristics of EVT as well as their interaction with maternal immune cells. We demonstrate that EVT are specialized cells whose properties are not imitated by HLA‐G–expressing surrogate cell lines. Studies using primary EVT are crucial for understanding maternal–fetal tolerance and development of pregnancy complications such as preeclampsia and miscarriages.