These authors looked at single institution outcomes for sacral agenesis (without spina bifida) with reference to renal function and bladder function. All had urodynamics either at diagnosis (56%) or soon after. Of 43 patients (23 female, 20 male), 37 had age recorded at diagnosis (19 were diagnosed before two months of age (five prenatally), 11 were diagnosed between 2-18 months and seven after 18 months). Twenty-three patients had serial urodynamics and 30% of these demonstrated detrusor overactivity. Twelve were voiding and 26 were carrying out clean intermittent catheterisation (CIC) with no data for the remainder. No patient developed end-stage renal disease or required spinal cord untethering. Twenty-one had no hydronephrosis on the most recent ultrasound scan (USS). Of those patients who underwent bladder surgery, three had a vesicostomy formed, 17 had ureteric re-implants, 10 had bladder augmentation and seven had continent catheterisable stomas. Bladder outlet procedures (slings, reconstructions, artificial urinary sphincter) were performed in 11 patients. The authors have demonstrated that sacral agenesis is usually diagnosed early although some are picked up at the time of delayed potty training. Most have a stable lower urinary tract innervation and only a small number demonstrate neuro-urological deterioration. The need for regular ongoing follow-up is essential but most children with sacral agenesis can be managed safely with relatively little intervention.