This is a review of current literature on unilateral strabismus surgery for small to moderate angle esotropia, exotropia, residual and consecutive strabismus and convergence or divergence insufficiency. The review considers recession surgery for eso / exotropia of angles up to 45PD eso and 40PD exo with recession amounts for exotropia up to 10mm and 8mm for esotropia. Success rates for esotropia are 80-100% and 51-84% for exotropia. Resection surgery is considered for exotropia up to 25PD of up to 10mm with a success of 80-95%. Resection surgery is considered for esotropia up to 25PD of up to 9mm with a success of 90-100%. The authors conclude unilateral recession or resection is safe, effective and predictable for small to moderate angle horizontal deviations. Advantages are fewer risks of complications and leaving other muscles for any subsequent surgery that may be needed. Disadvantages are the risk of lateral incomitance.