There are no national standards for the adequacy and complications of percutaneous renal biopsies. We developed local standards that have been used in a prospective audit of biopsies undertaken in a tertiary pediatric nephrology unit between January 1997 and December 2000. We compared outcomes of biopsies performed on inpatients with day care procedures. A total of 251 biopsies (113 transplant) were undertaken, 114 (46%) as day care procedures. Adequate tissue for diagnosis was obtained in 245 (97.6%), with a standard set at >95%. This was also achieved for a mean number of passes in native (<3 in 80%) and transplanted (<2 in 80%) kidneys. Eleven patients (4%) developed macroscopic hematuria (standard <5%) and none required transfusion. Delay in discharge occurred in 4 patients, and a further 4 returned to the ward post discharge. There was no significant difference in complication rates between inpatient and day care patients. Our local biopsy standards were met in this audit. Such standards could provide useful comparisons between units in national audit programs, as well as permitting the monitoring of individual performance as part of clinical governance. Day care procedures benefit the patient and family, as well as significantly reducing costs.