Deploying Zero Trust at the Enterprise Level

Working with big enterprise ZT, how does one engage the leadership effectively?  Is this about more tech?  Who holds the keys to the kingdom on budget?  Where does it make sense to start with a big time roll out?  How hard is it to get ZT in place?  How long is the journey?  Where does one go after they solve their first problem?  And why is Sean Connery on the line for this call?