The idea of this workshop at MPI für Physik is to explore and discuss in depth the determinations of alpha_S(m_Z) in the MSbar scheme from all the key categories where high precision measurements are currently being made. Since alpha_S is important for certain LHC measurements and since there are discrepancies in some determinations, such a workshop certainly seems in order. The main topic categories to be discussed in this 3-day workshop will be 1) Lattice QCD & Quarkonia 2) Tau Decays 3) e+e- Event Shape Distributions 4) R_had in Z-decays and EW Precision Observables 5) DIS and Global Fits 6) Future of alpha_S For each of the first 5 categories there will be a review talk by a person not involved in recent analyses and then a series of shorter invited talks by various groups who have been involved in recent analyses. The goal is to initiate and facilitate a lot of discussion between groups and to have opportunities to explain details that one would normally not be able to present at a conference, but which may have an important impact on the analyses. It is the aim to provide a detailed exposition on the differences in the results and error analyses for alpha_S(m_Z) within each method and between the different methods. Each talk will be followed by time for questions to the speaker and each of the main categories will include an additional designated 30min time for free discussion involving the audience, speakers and conveners. All attendees are encouraged to participate in the discussions and point at issues they think are important.