The hierarchy of Tax litigation in India is-
Assessment will be done by an Income - Tax officer; if the taxpayer is not satisfied by the assessment order, an appeal can be filed before the Commissioner of Income – Tax, any order passed by CIT (A) will be challenged before Income – Tax Appellate Tribunal; however an order of ITAT will only be challenged before High Court and Supreme Court on the substantial question of law whereas if an appeal is to be filed before Supreme Court, a certificate has to issue by the high court.