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In the field of cardiac electrophysiology, there is a universal desire: the discovery of a flawless diagnostic maneuver for supraventricular tachycardias (SVTs). This is not merely a wish but a shared odyssey. To improve diagnostic accuracy and achieve sufficient sensitivity and specificity, numerous diagnostic maneuvers have been proposed. However, each has its limitations and prompts a search for new diagnostic techniques. This continuous cycle of discovery and refinement, which we titled “SVT Quest” is reviewed in chronological sequence. This adventure in diagnosing narrow QRS tachycardia unfolds in 3 steps: Step 1 involves differentiating atrial tachycardia from other SVTs based on the observations such as V‐A‐V or V‐A‐A‐V response, ΔAA interval, VA linking, the last entrainment sequence, and response to the atrial extrastimulus. Step 2 focuses on differentiating orthodromic reciprocating tachycardia from atrioventricular nodal reentrant tachycardia based on the observations such as tachycardia reset upon the premature ventricular contraction during His refractoriness, uncorrected/corrected postpacing interval, differential ventricular entrainment, orthodromic His capture, transition zone analysis, and total pacing prematurity. Step 3 characterizes the concealed nodoventricular/nodofascicular pathway and His‐ventricular pathway‐related tachycardia based on observations such as V‐V‐A response, ΔatrioHis interval, and paradoxical reset phenomenon. There is no single diagnostic maneuver that fits all scenarios. Therefore, the ability to apply multiple maneuvers in a case allows the operator to accumulate evidence to make a likely diagnosis. Let's embark on this adventure! The SVT mechanism includes atrial tachycardia (AT), orthodromic reciprocating tachycardia (ORT) via an atrioventricular accessory pathway (AP), nodoventricular pathway (NVP), nodofascicular pathway (NFP) or His‐ventricular pathway, and atrioventricular nodal reentrant tachycardia (AVNRT). Diagnosis should be made in the following three steps: Step 1 involves differentiating AT from other SVTs based on observations such as V‐A‐V or V‐A‐A‐V response, ΔAA interval, VA linking, the last entrainment sequence, and response to atrial extrastimulus. Step 2 focuses on differentiating ORT from AVNRT based on observations such as tachycardia reset upon His‐refractory PVC, uncorrected/corrected postpacing interval (PPI) − tachycardia cycle length (TCL), differential ventricular entrainment, orthodromic His capture, transition zone analysis, and total pacing prematurity (TPP). Step 3 characterizes ORTs via concealed NV/NFP and HVP‐related mechanisms based on observations such as V‐V‐A response, atrioHis (AH) interval, and paradoxical reset phenomenon.