Studies assessing space use are often descriptive but sometimes lack guidance for managers whose objectives include altering wildlife abundance through habitat management programs. The concept of usable space (i.e., species-specific permanent cover situations that maximize fitness) collapses commonly used home-range estimates (e.g., kernel estimators) by excluding cover types contained within individual home ranges that lack direct evidence of use and by reducing cover types containing large areas but small proportions of location estimates. In theory, estimates of usable space provide a potentially more accurate biological representation of space use compared to kernel estimators and provide guidance for managing avoided cover types (i.e., used in a proportion less than available). Our objectives were to compare white-tailed deer (Odocoileus virginianus) space use under the kernel and usable-space methods and to discuss the implications of cover conversions under the usable-space concept. Using radiomarked adult female deer (n = 20) in south central Michigan, USA, during 2004–2006, we found that fixed-kernel home-range estimates (x = 77.5 ha ± 9.6 SE for the agricultural growing season, x = 140.4 ha ± 23.4 SE for the nongrowing season) included cover types with no evidence of use (e.g., no telemetry locations). Usable-space estimates (ha) were approximately 75% that of kernel home ranges and were dominated (approx. 87%) by upland deciduous forest, lowland shrub, agriculture, and coniferous cover types. Under the assumption that deer densities are positively correlated with the amount of usable space, we provided several cover-conversion scenarios (i.e., habitat manipulation) that would theoretically change deer densities on our study area by increasing or decreasing the amount of usable space. Effects of land-use changes (e.g., increasing urbanization, such as on our study area and throughout much of the midwestern United States) on usable space and inferences on deer population responses may also be assessed using our approach. Regardless of the wildlife species being managed, decisions regarding habitat manipulation are often constrained by several factors (e.g., social, edaphic) and managers should consider ecological processes (e.g., vegetation succession) and implications on broader objectives (e.g., biodiversity conservation).