This thesis presents evidence on two related sets of patterns and relationships. First it show commercial dairy farm size distributions and related to farm management and operator characteristics. Second it shows how gender demographics of dairy farm operators have changed over time and relationships between farm size and farm operator characteristics related to gender and marriage between farm operators. The data draws on the four Census of Agriculture from 2002 through 2017 and the six major dairy states—California, Idaho, New Mexico, New York, Texas, and Wisconsin.As the trend of farm consolidation continues within the dairy industry, it remains imperative to present evidence of ongoing farm size trends with geographic distinctions. There is a clear trend of increasing herd sizes across all states and a decrease in the number of commercial dairies. Herd size patterns and trends vary greatly by state and this research finds that none of the six states studies follow either of the two common skewed parametric densities often used for firm size. Moreover, there remains little evidence that the U.S. dairy industry is becoming bimodal. The diversification of sales has a positive relationship with farm size. Farm operator characteristics, such as age and off farm employment, tend to have either a slightly negative relationship with size or no relationship with size. This research finds that the old assumption that dairy farms are traditionally run by men is shifting with increase representation of female dairy farm operators. Recent data shows an increase in the share of commercial dairy farm operators who are female and an increase in the share of commercial dairies with at least one female operator. Census of Agriculture data also show that the presence of female operators on a dairy farm and a spousal run dairy has negative correlation with the commercial dairy farm size. Commercial dairy farms run by spouses and that include women may make management decisions that differ from those exclusively run by men.