Colic is commonly encountered in the post-foaling mare and can pose a diagnostic challenge for the equine practitioner. Many conditions can contribute to signs of colic in these mares, including conditions of the gastrointestinal, reproductive and genitourinary tracts. Diagnostic workup is similar to that of most other cases of colic, with additional attention paid to the udder, vulva and vaginal vault. Transabdominal ultrasound examination is important in the assessment of these mares and allows identification of key features for diagnosis. Conditions of the gastrointestinal tract include large colon displacement or volvulus, caecal tympany, impaction, necrosis and rupture, small intestinal strangulation through a mesenteric rent, large or small colon impaction, bruised bowel, diaphragmatic herniation, ischaemic necrosis of the descending colon after tearing of the mesocolon and rectal prolapse. Aggressive therapy is generally required for most of these conditions and prognosis is variable.