The proliferation of plastic has created a wicked global sustainability challenge. From the extraction of fossil fuels to end-of-life management and pollution, plastic imposes significant negative impacts to human health, economic well-being, and the environment. One proposed solution is to replace conventional plastic with biomass-based plastics and plastic alternatives (BBPAs), such as paper or bio-based plastics. While these products may have advantageous properties, they require biomass as a feedstock. Given the scale of the plastics problem, this biomass demand may be significant. In my dissertation, I evaluate the magnitude of biomass required, and assess the potential impact of this biomass demand on global land use. After examining the scope and the scale of the problem in chapter one, I evaluate the assumptions that have been made regarding the land-use impacts of BBPAs in chapter two. In chapter three, I use a global land-system model (CLUMondo) to evaluate the potential land-use change of large-scale production of BBPAs. In chapter four, I evaluate how certification schemes could be used as a policy tool to mitigate the land-use impacts of bio-based alternatives. I find that the current studies evaluating the land-use impacts of these products make optimistic and unrealistic assumptions regarding land-use. Using a global model, I show how high production scenarios of BBPAs could induce significant land-use change at the global level. Finally, I demonstrate that reliance on certification schemes would likely be insufficient to prevent negative impacts from this scale of land change. Overall, this dissertation suggests that large-scale replacement of plastic with BBPAs could incur significant land-use impacts. Policies designed to mitigate the impacts of plastic need to account for this impact to land-use, lest they risk substituting one global problem for another.