Mentally recall a meeting in which one of your colleagues was passionately promoting his point of view. Picture him leaning forward, his voice pitched in excitement, his skin flushed as he’s adamantly pressing on about his idea. Remember how you deciphered the signs of his intense commitment: voice, posture, pace, facial expression, and word choice. You observed these details and made some conclusions about his commitment, intent, and anxiety. Great leaders are great observers. Yes, you have to articulate vision and mission and you have to effectively express goals and shape processes. But if you don’t learn to observe, you won’t fully activate all your leadership responsibilities. Strong observation skills lie at the heart of leadership abilities such as effective communication, engaging interpersonal skills, influencing people, managing change, managing group dynamics, and selling (getting buy-in) ideas, plans, and strategy. Modern leadership depends on relationships; it works in the context of rapport, bonding, and association. Meaningful relationships emerge when you know and understand the other.

Here are 5 reasons why observing others and consequently understanding them is key to your leadership effectiveness.