Controlling is the process of ensuring actual performance matches planned performance. It involves setting standards, measuring actual performance, comparing the two to identify deviations, analyzing the causes of deviations, and taking corrective actions. This helps accomplish organizational goals, judge standard accuracy, efficiently use resources, improve employee motivation, ensure order and discipline, coordinate activities, and support better decision making. However, controlling faces limitations like difficulty setting standards for intangibles, limited control over external factors, employee resistance, and high costs for small organizations. The controlling process consists of five steps - setting standards, measuring actual performance, comparing to standards, analyzing deviations, and taking corrective actions.