Fibroblast's are the predominant cells of mesenchymal origin, recognized by their association with collagen fibre bundles that are the workhorse of the connective tissue. These cells are biologically dynamic & morphologically heterogeneous, and they exhibit diversity in their structure, depending upon the location. These specialized cells induce secretion, maintenance & reabsorption of collagenous extracellular matrix. They also serve pivotal roles in wound healing, inflammation, angiogenesis, cancer progression and pathological tissue fibrosis. This book provides an overview of fibroblasts in health and disease.