Definition: extradition is the formal process by which one state (the requested state) surrenders a person found in its territory to another state (the requesting state) that accuses him of a crime or seeks his punishment — the procedural complement of jurisdiction (jurisdiction says "we may try" extradition moves the body to where the trial can occur).
Nepal's framework: the Extradition Act, 2046 (1988) governs extradition to and from Nepal — extradition generally proceeding on treaty relations (the treaty with India — originally under the 1950 framework, treaty 1963, revised in 2013 — being the principal operative instrument; extradition arrangements with other states negotiated case-by-case or under multilateral conventions where applicable). The Act's scheme (describe by its principles, per the syllabus's method): request through diplomatic channels; the offence's dual criminality (an offence punishable in both states); the political-offence exception; nationality and humanitarian considerations; judicial examination before surrender; and the rule of speciality (the person surrendered may only be tried for the extradited offence).
General principles of extradition law (the portable checklist):
1. Extradition is a matter of treaty and comity, not right — no general duty to surrender absent obligation (aut dedere aut judicare conventions aside);
2. Dual criminality required;
3. Political offence exception (with carve-outs in modern treaties for terrorism, hijacking, grave violence against heads of state — the 2013 Nepal–India revision's controversies included the exception's scope);
4. Speciality rule;
5. Non-extradition of nationals (many states, civil-law style, decline to surrender their own citizens — offering instead domestic prosecution on the active-personality principle);
6. No extradition for military/religious offences, or where the death penalty/he political persecution risks offend the requested state's public order (refus de l'extradition for inhumane consequences);
7. Double jeopardy (ne bis in idem) bar where the person was already tried for the same facts.
The alternative to extradition: deportation (immigration removal) — used where no treaty duty runs (its legality debated where used to accomplish what extradition would forbid); and mutuallegal assistance (evidence, not persons — the modern transnational-criminal-law toolkit — cross- reference Public International Law-I).