Lactate measurements have been evaluated in intrapartum fetal surveillance for some 30 years. However, it was not until reliable, handheld, microvolume devices were launched during the 1990s that lactate became a clinical option. Retrospective data suggest that lactate determinations in fetal scalp blood are better than pH for predicting severe neonatal morbidity. A randomised controlled trial comparing these two measurements found lactate to be more favourable in clinical practice in terms of less sampling failure and reduced time from the decision to do a fetal scalp blood sample to the clinician receiving the result. At present, a large multicenter randomised control trial is in progress in Sweden to compare lactate and pH measurement for the clinical management of suspected fetal compromise. Main end-points in the study are metabolic acidemia or pH <7.00 in cord arterial blood at delivery. Results are likely to be available in 2-3 years time.