Generalized pustular psoriasis (GPP) is a chronic, systemic inflammatory disease accompanied by high fever and general malaise. Diffuse erythema and swelling of the extremities occur, with multiple sterile pustules all over the body in GPP patients. GPP often relapses over the lifetime and can be life-threatening. Recent discoveries of the underlying molecular genetic basis of many cases of this disorder have provided major advances to clinicians and researchers towards an understanding of the pathomechanism of GPP. However, the therapeutic management of GPP still faces many challenges and much uncertainty, and an evidence-based review summarizing the available clinical data on the management of this heterogeneous disease is needed. The present review addresses challenges regarding the precise clinical diagnosis and evaluation of clinical symptoms in GPP. In addition, we update and briefly summarize the current understanding of molecular pathomechanisms behind GPP as an autoinflammatory keratinization disease. Recent publications have clarified the genetic backgrounds of patients with GPP and ethnic differences in predisposing factors. Although there are ethnic differences in the prevalences of these pathogenic alleles, from recent reports, at most 60.5% (IL36RN), 5.9% (CARD14), and 10.8% (AP1S3) of GPP patients have the mutations/variations of these genes. All the reported biologics studied seemed effective and relatively well tolerated. Although it is difficult to evaluate therapeutic efficacy from studies on just a few cases, recent findings suggest that biologics can be a useful, powerful tool for controlling skin and systemic inflammation in GPP and for improving the quality of life of GPP patients.