What has as its purpose - to collate key information for senior management on those change initiatives that will deliver the greatest contribution to the strategic objectives?

Which of the following are 'keys to success' of the organizational governance practice?

1. A shared vision for the portfolio

2. Focus on senior management

3. Business cases and progress are reviewed regularly

4. Shared understanding of the governance structure and processes

Identify the missing words in the following sentence. Dependencies in a complex portfolio environment [?] but if not managed effectively can represent a serious risk to delivery.