ABSTRACT: As the importance of planning and scheduling of a mining operation become apparent, there has beenan increasing use of sample data to estimate the grade and amount of material to be mined. Concordantlyimportance of reliable mineral resource and reserve estimations has increased. Since the start of themodern mining era by the JORC Code, there has been an increasing tendency to regulate estimationand public reporting of mineral resources and reserves. These codes do not attempt to regulate eitherthe method of estimation of the resource/ore reserve or the classification technique, but rather providea system for estimation and classification of tonnage and grade estimates according to geologicalconfidence and technical/economic considerations. These reporting standards are considered by stockexchanges and finance organizations to represent best practice and form the minimum standard for publicreporting of exploration results, mineral resources and ore reserves. The national reporting codes areinvolved in international negotiations on reciprocity of reporting definitions and standards which havebeen underway for some years and are still ongoing. Meanwhile, stock exchange listing rules now define a“recognized mining professional” in similar terms to a CP, except that the person must have “membershipof a recognized overseas professional body that has agreed to sanction the person if the person does notcomply with rules”. This review paper has been written to summarize the latest developments in mineralresource estimation and reporting practices, describe some best practices.