This instruction lays down comprehensive guidelines to ensure uniform, fair, and non-intrusive investigation practices by CGST field formations, while safeguarding ease of doing business for regular taxpayers. It prescribes approval-based initiation of investigations, coordination among CGST, DGGI, and State GST authorities to avoid parallel proceedings, and special safeguards for cases involving interpretation issues, large corporates, PSUs, or matters before the GST Council. The instruction emphasises preference for official correspondence over summons, avoidance of fishing enquiries, and prohibition on seeking information already available on the GST portal. Clear protocols are laid down for issuance of summons, recording of statements, documentation, and timely conclusion of investigations, ordinarily within one year. A grievance redressal mechanism is also provided, designating senior officers to address taxpayer grievances during investigations. The instruction aims to ensure legally sustainable enforcement while preventing harassment and unnecessary litigation.