In your own words, define what successful leadership is and how leadership and management differ in an office setting.

In my opinion, successful leadership is an ability of a leader to change their traits and leadership styles with changing environment and circumstances. Hence, situational leadership in my opinion is the most effective form of leadership style. Under this approach, leaders may respond or react to a particular situation by- commanding, persuading, coaching, participating, delegating or however they believe is the best approach to handle the situation. Hence such leaders are defined by their flexibility and adaptability. Also, such leaders change their leadership style or behaviour towards handling or managing diversified employees who have different personality traits.
By being 'Directive', a leader can direct and guide the team members to perform better. A leader's counsel or advice can help team members to realize and rectify their mistakes. Hence, it increases their productivity and performance level.
By being 'supportive'; the leader tries to support and help the team members in overcoming their fear and challenges in the organisation. Such leadership can be influential because such leaders by encouraging team members, building interpersonal relations increases the trust level with them. Hence, employees feel more connected and engaged to their leaders and organisations.
By being 'participative', a leader actually induce democracy and freedom in the work process. He encourages the team members to involve and provide their suggestion or opinions while taking an effective and worthy decision for the long term sustainability of the organisation.
By being 'achievement oriented', a leader expects their employees to perform at their highest level, and alps shows confidence in their ability to meet this expectation. He also trains and invest his efforts in increasing their skills and abilities to perform better. Leader try to enhance the productivity of employees by regularly reviewing and evaluating their performance. And also provide necessary feedback to better their scope of performance. This is my definition of an effective leadership style.
The main difference between the leader and manager is that leaders have people that follow them, while managers have people who simply work for them. For any company to be successful and profitable, it needs management that can plan, schedule, organise and coordinate its staff, whereas leaders also inspire and motivate them to perform to the best of their ability.