According to the PMBOK Guide, 7th edition, section 4.3.2.1, when a project faces a technical issue that requires specialized knowledge or expertise, the project manager should consult with external subject matter experts (SMEs) and the team to find a solution. External SMEs are individuals or groups who have specialized knowledge or skills related to a specific aspect of the project, such as aerospace design. They can provide valuable insights, recommendations, and guidance to the project team. The project team consists of the project manager and the project staff who are responsible for performing the project work. They have the most knowledge and experience about the project and its deliverables. The project manager should involve both the external SMEs and the team in the discussion of the technical issue, as they can contribute different perspectives and ideas to resolve the issue. The project manager should also communicate the issue and the proposed solution to the project sponsor and other relevant stakeholders, but they do not need to be part of the initial meeting.
References:
PMBOK Guide, 7th edition, section 4.3.2.1
PMP Exam Content Outline, Domain II: Process, Task 5

In a project, especially when a new approach is being used, it is crucial to ensure that all key stakeholders, including the project sponsor, are aware of and understand the approach. This is because these stakeholders often have a significant influence on the project's success. By explaining and communicating the new approach, the project manager can ensure that everyone is on the same page, which can help to prevent misunderstandings and conflicts later on. This is also in line with the PMBOK Guide's emphasis on the importance of effective communication in project management. References: Project Management Body of Knowledge (PMBOK) Guide, 6th Edition, Section 10: Project Communications Management

In an agile project, collaboration and team input are crucial for success. Before sending details and estimates to the client, the project manager should engage with the team to gather their insights and expertise. This ensures that the project plan reflects a realistic approach, considering the team's views on dependencies and potential risks. Agile methodologies emphasize the importance of team collaboration and iterative development, which includes regularly revisiting and adjusting plans as the project progresses1234.
References:
Agile Communication: Techniques, Examples and Best Practices1
How to Nail Your Agile Communication Plan2
How to Communicate and Collaborate with Stakeholders in Agile Projects3 The Agile Project Management Approach4 V

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