Hi Will
During the initial phase of your deployment, I recommend having your BB’s reporting to your deployment leader, and utilising your consulting partners resources as MBB’s (unless you are recruiting MBB’s externaly to your organisation).
Once you have trained your own MBB’s, then have your BB’s reporting to the MBB’s, with your MBB’s reporting to the deployment leader directly (with dotted line to the various business leaders). Each MBB should be assigned to a business leader and is accountable to assist the business leader in delivering their strategy.
Once your deployment has matured (3-4 years), then you can consider changing the reporting structure to dotted line to deployment leader and solid line to business leader.
This approach will ensure alignment with your corporate objectives, while at the same time get the necessary traction of your deployment. However, as each company culture is unique, I recommend that you make this decision in your up-front design team phase.
Just my thoughts.
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