Thus, unlike cytotoxic T lymphocyte (CTL) epitopes and their escape mutations, which are frequently predicted by the association of viral sequence polymorphism and HLA alleles, Nab epitopes and escape pathways in Env can be inherently difficult to identify based on sequence alone. We have therefore undertaken a molecular approach to define these in subtype C HIV-1 Env during early infection. Using a pseudovirus-based assay that facilitates evaluation of individual, patient-derived Envs, we analyzed the neutralizing ability of longitudinal plasma samples against contemporaneously-derived, autologous Envs from two subtype C seroconvertors who generated potent Nab against the infecting Env. Sequential neutralization escape variants emerged in both patients, and we used Env domain exchange and sitedirected mutagenesis approaches to map the pathways involved in Nab escape at multiple time points throughout the first two years of infection. Nab escape in these two patients was driven by V1V2dependent and -independent pathways, and these pathways exhibited different levels of stability over time. Yet, spatial representation of the sequence changes in gp120 indicated that immune pressure was directed at the same Env regions in both subjects. The derivation of autologous monoclonal antibodies (Mabs) from one patient demonstrated how a single potential glycan change in V1V2 afforded simultaneous resistance against multiple antibodies. These studies therefore provide a detailed look at Nab escape in subjects recently infected with the most predominant subtype worldwide, and demonstrate that the flexibility of Env facilitates the use of multiple mechanisms.