The meniscus plays a critical role in load transmission, stability and energy dissipation in the knee joint. Loss of the meniscus leads to joint degeneration and osteoarthritis. An increased understanding of the degenerative changes that occur after meniscectomy made clear that it is beneficial to save as much meniscal tissue as possible. Meniscal repair has become a standard procedure, and partial resection of damaged menisci should be performed as sparingly as possible. However, not all damaged menisci can be treated by partial resection or by repair, making a total meniscectomy inevitable. In these cases, replacement of the resected meniscal tissue by an implant might avoid the articular cartilage degeneration. Different types of meniscal substitutes, such as allografts, collagen, permanent synthetic scaffolds, and biodegradable scaffolds, have been used in experimental and clinical studies. This review highlights the research on these meniscal substitutes and shows that current research is mainly focused on a biological tissue-engineering approach either with or without additional cell-seeding techniques.