This field involves the managing of a department or a business. Effective managers are good planners and good organisers, and are able to influence others positively so that goals are achieved and targets are met. Effective managers have a strong self-belief, a lot of energy and an optimistic outlook. A person cannot become a manager without the necessary qualifications and experience. Managers on the highest level in the corporate world have a good knowledge of accountancy, economics, commercial law and other specialised knowledge. In addition to these qualifications, they possess a sound knowledge of the business, which can only be acquired over a period of time. Managers in specialist areas of expertise are some of the fastest growing and most challenging - these include: Marketing Manager, Production Manager, Hotel Manager, Human Resource Manager, etc.