Seven infertile women, in whom interstitial fallopian tube obstruction (IFTO) was suspected at hysterosalpingography and who were recommended for surgical evaluation and treatment, were treated with catheterization techniques. Selective salpingography with ostial injection demonstrated tubal patency in two patients; direct intratubal salpingography demonstrated patency in another patient. Four patients with a true IFTO underwent fallopian tube recanalization: in the first two, a small soft-tipped guide wire was used, and in the other two, a guide wire and 3-F catheter were used. The suggested catheterization techniques have the potential to make evaluation and treatment of IFTO more efficient, safer, and less expensive than presently used methods.