Background Context. Different minimally invasive approaches to the lumbar spine have been proposed but they can be associated with increased risk of complications, steep learning curve and longer operative time. Purpose. To report the complications associated with a minimally invasive technique of retroperitoneal anterolateral approach to the lumbar spine. Study design. Retrospective study of 179 patients who underwent anterior oblique lumbar interbody fusion (OLIF). Methods. A total of 179 patients with previous posterior instrumented fusion undergoing OLIF were included. This muscle-splitting approach consists in anterolateral exposure through a 4 cm incision followed by placement of a PEEK cage filled with bone graft and/or substitute. Results. Patients were aged 54.110.6 years with BMI of 24.84.1 kg/m2. Length of follow-up was (0.90.7 years), including 17 patients with a minimum follow-up of 2 years. A left-sided approach was done in 174 patients. The procedure was performed at L1–2 in 4, L2–3 in 54, L3–4 in 120, L4–5 in 134 and L5-S1 in 6 patients. It was done at 1 level in 56, 2 levels in 107, and 3 levels in 16 patients. Operative time and blood loss were respectively 32.513.2 min and 57131 cc per level fused. There were 19 patients with single complication and one with two complications, including two patients with postoperative radiculopathy after L3–5 OLIF. There was no abdominal weakness or herniation. Conclusion. Minimally invasive OLIF can be performed easily and safely from L2 to L5, and at L1–2 and L5-S1 for selected cases. Up to 3 levels can be addressed through a “sliding window”. It is associated with minimal blood loss and short operative time. The risk of complications is similar to that reported for traditional anterior approaches, with the advantage of decreasing the risk of abdominal wall weakness or herniation