To report the safety and effectiveness of selective laser trabeculoplasty (SLT) using the SLT mode of the VISULAS^® green laser in patients with primary open-angle glaucoma (POAG). Twelve months results are presented. Retrospective extension in 4 German centers of an initially prospective interventional multicenter 3-month clinical investigation using the VISULAS^® green SLT (Carl Zeiss Meditec AG, Jena, Germany) in patients with POAG who either needed treatment escalation or commenced treatment and had an IOP ≥ 17mmHg at baseline, with no previous glaucoma or other ocular surgery. Non-overlapping laser spots (100) were applied in a single session to 360° of the trabecular meshwork (TM). Glaucoma medications were not changed up to the 3-month visit. From 3 to 12 months, patients were managed according to routine standard of care. Outcome measures included IOP reduction, further glaucoma interventions, and adverse events from baseline to month 12. 25 eyes of 25 POAG patients (mean age 65.8 ± 8.5; modified intention to treat – mITT –group) were included in the extension study. Six eyes (24%) underwent additional glaucoma treatment or changed glaucoma therapy; the remaining 19 eyes (76%) had stable glaucoma therapy (SGT group) with no further glaucoma intervention or change in glaucoma medications (mean number of preoperative glaucoma medications: 2.3 ± 1.34). In the SGT group, mean baseline IOP (mmHg) was reduced from 20.0 ± 2.11 at baseline to 17.4 ± 3.25 and 16.2 ± 1.83 at 6 to 12 months, respectively (p < 0.0001): 52.6% had ≥ 20% IOP reduction at 12 months. Potential device- or procedure-related adverse events were mild to moderate and resolved without sequelae. SLT performed with the VISULAS^® green laser reduced IOP in eyes with POAG up to 12 months with no relevant safety issues. The results are comparable to other reported SLT studies.