How do you make your idea of a change that is needed, an idea that the others own? Introduce the idea, a drip at a time. During your interchanges with others, you make subtle suggestions about the change. As the others gets used to the idea and if it is consistent with their ideas, they will adopt it as their own. Harvey called that the drip method.
If you are working with knowledge workers, they will not respond to directives, but will listen to subtle suggestions that are repeated frequently.
For example, I had a client that I wanted to take a different approach to dealing with decentralization of computer operations and development. During several meeting I told him stories about an article I had read about a different approach. As our work progress, he adopted the idea and really owned the solution.
If you want your team to be more innovative and think outside the box, be patient and keep talking about the idea and telling stories. Be subtle and indirect. One way is to make it fun and challenging. As you are persistent, the environment will change and the innovation will become their idea.
I always found that patience and subtle suggestion really helped. Think of it as "drip, drip, drip." Inspiring change can be very rewarding.