This approved BA thesis discusses economically realizable Open Access (OA) publishing models. First, the advantages of and need for OA in scholarly discourse will be addressed. Afterwards, I will discuss the routes to widespread gold (access provided by publishers) and green (access provided by repositories) OA. By drawing from examples in the contemporary landscape of academic publishing, several routes  to universal free access to scientific literature (i.e. the green route to gold OA, the hybrid route to gold OA, and gold OA enabled by authors, libraries, institutions and publishers) will be elaborated on and compared.