As a leader, you are building the culture every single moment of every single day in your organisation. Your behaviour more than any other single thing creates the culture of your workplace. People look at you and say 'OK, that's what he or she expects'
If you're a junior doctor, the medical students learn from you, if you're a registrar both the medical students and the RMOs are watching how you behave and will emulate the words you use, the way you approach workplace relationships and how you treat others. As a consultant, will be expected to have the courage to both do the right things and pull up those whose behaviour is unacceptable.
Leadership character starts with you.