DNA is packaged tightly creating an environment unconducive to transcriptional activation. Chromatin modifications must be made in order to facilitate transcription in eukaryotes. Histone deacetylases (HDACs) have become an important focus in research due to their role in many fundamental processes including differentiation, growth arrest and apoptosis. Previous research has shown that HDACs can influence transcription factors and play a crucial role in bone homeostasis. This study aims to understand the role of HDAC9 and HDAC11 on osteoclast differentiation and activity. While few studies have been able to identify HDAC11’s role in osteoclastogenesis, it has been shown in previous studies that overexpression of HDAC9 inhibits osteoclast differentiation while conversely loss of HDAC9 expression leads to enhanced osteoclastogenesis. To investigate the effects of HDACs 9 and 11, I conducted a series of experiments and found loss of HDAC9 or HDAC11 expression leads to enhanced osteoclast differentiation and elevated bone resorption.