The Single-window system is a trade facilitation idea. In simple words, it allows a user to get sufficient information from one source. As such, the implementation of a single window system enables international (cross-border) traders to submit regulatory documents at a single location and/or single entity. Such documents are typically customs declarations, applications for import/export permits, and other supporting documents such as certificates of origin and trading invoices.
The main value proposition for having a single window for a country or economy is to increase the efficiency through time and cost savings for traders in their dealings with government authorities for obtaining the relevant clearance and permit(s) for moving cargoes across national or economic borders. In a traditional pre-single-window environment, traders may have had to contend with visits and dealings with multiple government agencies in multiple locations to obtain the necessary papers, permits, and clearances to complete their import or export processes.