Earlier research has focused on technical debt (TD). While numerous issues connected to non-technical aspects of software development (SD) that are equally worthy of”debt” status are neglected. Simultaneously, these types of debts regularly develop significant challenges to be addressed, demonstrating that the debt metaphor may be used to reason about elements other than technical ones. It motivates us to create the new umbrella term”Non-Technical Debt” (NTD) to investigate people, processes, culture, social, and organizational concerns under its cover. All types of debt are similar in some ways, and they are often caused by making risky decisions. Therefore, ignoring any one dimension of debt can have severe consequences on the successful completion of SD projects. This study investigates recent literature on the current state of knowledge about NTD, its causes, and mitigation strategies. By using a thematic analysis approach, we found five NTD types (i.e., people, process, culture, social, and organizational). We further identified their accumulation causes and discussed remedies for mitigation.