The use of alternative medicine in chronic rhinosinusitis (CRS) continues to increase in popularity, for the most part without meeting the burden of being based on sound clinical evidence. New and emerging treatments, both natural and developed, are numerous, and it remains a challenge for otolaryngologists as well as general practitioners to keep up to date with these therapies and their efficacy. In this systematic review, we discuss a number of alternative therapies for CRS, their proposed physiologic mechanisms, and evidence supporting their use. This analysis is based on our review of the English-language literature on alternative therapies for CRS (we did not include any therapies that are already recommended by accepted professional bodies). Data collection was performed using the PubMed database (not restricted to MEDLINE due to the nature of the subject matter), the Cochrane databases, and bibliography searches. We found that while many of the alternative therapies we reviewed might have a firm basis in science, they lack any clinical evidence to support their use specifically for CRS. Some emerging therapies, such as therapeutic ultrasonography and phonophoresis, show some promise, based on a growing body of positive evidence. In addition, the use of baby shampoo, thyme honey, and bromelain additives to saline lavage in CRS are all supported by clinical evidence, as is Sinupret, an oral preparation that contains echinacea. However, higher levels of evidence gleaned from large, well-designed, prospective, randomized, controlled trials are needed before any of these therapies can be recommended.