What is the proper sleep position for infants to reduce SIDS risk?

Sudden Infant Death Syndrome (SIDS) — sudden unexplained death of infants <1 year — was reduced by 50%+ through the AAP 'Back to Sleep' campaign (now 'Safe to Sleep'). Recommendations: (1) Supine (back) sleep position for every sleep until age 1 — significantly reduces SIDS risk; the position with strongest evidence; (2) Firm sleep surface — safety-approved crib mattress; no waterbeds, couches, soft surfaces; (3) Bare crib — no blankets, pillows, stuffed animals, bumpers, soft toys, sleep positioners; (4) Room-sharing but not bed-sharing — infant in separate sleep space in parents' room ideally for first 6-12 months; bed-sharing increases SIDS risk; (5) Avoid overheating — light clothing, room temperature 68-72°F; sleep sack instead of blanket; (6) Avoid prenatal smoke exposure and infant smoke exposure; (7) Breastfeed when possible — reduces SIDS risk; (8) Pacifier use at sleep times — reduces SIDS risk (after breastfeeding is established if breastfeeding); (9) Routine immunizations — reduce SIDS risk; (10) Avoid alcohol and drug exposure. Tummy time during awake/supervised periods (not for sleep) is important for development. Side sleeping is NOT a safe alternative — infants can roll to prone. Once infant can roll independently, they can be left in the position they assume but should be placed supine to start.