Hi Joan,
One of the first things you would need to look at is whether the organization has a competency framework and what the essential competencies are for a particular level of employees. Most organizations these days base a lot of their training (leadership being a huge chunk) on the competency framework. In case the organization does not have one, the starting point would be to do an intervention to build the same.
Post that, the critical competencies thus identified can be a part of the Leadership Program. Anywhere between 3 days to a week of in-class as well as one-on-one coaching form part of leadership training programs.
If you wish to know more, I request you to drop in your email id, and if you have any further questions.
Regards,
Rohan