Carbon fiber reinforced polymer (CFRP) composites are increasingly being used to strengthen structures and to retrofit existing structures. CFRP composites are used in various industries: construction, automotive, and many others. This literature review has shown that CFRP composites find numerous practical applications. Improving structures by reinforcing them with CFRP composite is an innovative approach in design. This review aims to explore the current state of the art in the types of structures that can be reinforced with CFRP, and modifications to the CFRP composite as an additional aspect to increase the strength of the reinforced structure. It has been shown that regardless of the type of reinforced material, the most critical element in this connection is the bonded joint. Proper surface preparation and the use of an appropriate adhesive are also important.