Narrowband-UVB (NB-UVB) is a non-ionizing radiation therapy that uses specific wavelengths (308-313 nm) of light as therapeutic treatment for various dermatologic conditions including psoriasis, atopic dermatitis (AD), vitiligo, and alopecia areata. Clinical trials on the use of NB-UVB for these diseases began in the 1990s, and newer trials have compared different phototherapies (NB-UVB, broadband-UVB, UVA1, psoralen-UVA, excimer light) with one another as well as with other treatments. We reviewed our experience with NB-UVB, in addition to data from a PubMed search of phase I, II, and III clinical trials, as well as review articles and meta-analyses, for relevant literature published between January 2015 and September 2021 utilizing the following key terms: phototherapy, narrowband-UVB, psoriasis, atopic dermatitis, vitiligo, and treatment. The search was subsequently expanded to include additional relevant terminology. In multiple clinical trials, NB-UVB therapy was efficacious and safe for use in psoriasis, vitiligo, AD, and many other dermatological conditions. The use of phototherapy is efficacious as an adjuvant therapy, or a useful option for those who have failed first-line treatments. In head-to-head comparisons, both NB-UVB and UVA1 had greater improvement in scalp and palmoplantar psoriasis in patients, compared to other phototherapies. When studied as an adjuvant therapy, NB-UVB was, for the most part, statistically significant and clinically meaningfully effective. No studies reported any serious adverse events due to NB-UVB therapy; however care should be taken to prevent burns. Our team’s studies included a multicenter open trial of 308 nm UVB therapy; 72% of patients achieved at least 75% reduction in Psoriasis Area and Severity Index (PASI75) after a mean 6.2 treatment sessions. UVB phototherapy was safe and effective in this study. NB-UVB therapy is both safe and efficacious for use in patients with psoriasis, AD, vitiligo, and various other dermatological conditions. Phototherapy, especially home NB-UVB, may offer patients a lower-cost, more accessible option compared to office phototherapy or to biologic treatment.