A fundamental part of behavior is understanding how and why individual decisions are made. These decisions influence mating behavior, and can ultimately impact survival and reproductive success. An element oft overlooked is how the spatial environment provides an immutable backdrop and context for all such interactions. In this body of work, I explored how spatial and social contexts affect individual mating tactics, social dynamics, and underlying neural mechanisms in prairie voles (Microtus ochrogaster). First, I describe how sex-specific cognitive demands influence neural and behavioral phenotypes. I showed that males have better spatial performance and also decreased nonapeptide receptor expression in a crucial memory region of the brain. Next, I used an ecological model to demonstrate the dynamic nature of reproductive decision-making. I modeled the most advantageous times for males to seek extra pair copulations (EPC). I found that as EPC-seeking in the population increases, the optimal strategy shifts from monogamous to more promiscuous tactics. Then I provide evidence that intensity of intraspecific competition is an important factor shaping spatial memory. By manipulating intensity between contexts in semi-natural outdoor enclosures, I found that males demonstrate better spatial memory within male-biased contexts, indicating that spatial memory is particularly relevant for male-male interactions. Next, I asked how differential access to mates influences mixed paternity and overall reproductive success in female prairie voles living in semi-natural outdoor enclosures. When males outnumber females, females have fewer mating partners yet when females outnumber males they have multiple partners and high rates of mixed paternity. Lastly, I describe how socio-spatial learning ability impacts male mating tactics in outdoor enclosures. I tested whether cognitive ability is predictive of results from a chosen mating tactic. My data emphasize that individual mating tactics are uniquely influenced by context and cognitive abilities. Taken Together this research highlights the importance of understanding space use from multiple levels of investigation including brain, behavior, and semi-natural field studies. Through this integrative approach I developed a nuanced understanding of how space use impacts neural mechanisms, cognitive ability, and reproductive decisions.