As a project manager how do you handle procurements procedures?

Procurement management plan should have all the strategies to handle all the types of procurements related to that project and it is not just project managers duty to manage and handle procurements a relationship manager will also plays an important role.

Identifying requirement and usage of procurements for rite time and optimum utilization plus quality assurance and control will help managing procurements in better way

Note* the terms for procurements should be clear and agreed with respect to Quality, Quantity, Time and Cost when deciding

Every company has a slightly varied procedure, but I'd definitely ensure that I'm in sync with the operations team.

Project procurement require flexibilities without loosing control over the process,  policies and procedures to be for its effectiveness in costs reduction.

Procurement is the acquisition of goods, services or works from an external source. It is favourable that the goods, services or works are appropriate and that they are procured at the best possible cost to meet the needs of the acquirer in terms of quality and quantity, time, and location. Corporations and public bodies often define processes intended to promote fair and open competition for their business while minimizing exposure to fraud and collusion.

The best way is to involve the Procurement department of your company right into the project from the outset and keep them abreast of all key milestones; like design clearance, Kick-off meeting, completion of different phases, arrival of raw materials at vendor's facilities, inspection plans and finally the logistics. The procurement guy dedicated for this task will not only help you out but he will also gain a lot of new project insights. I am telling you this based on my past & present working practices. 

The best solution is to consult with the Contractor Officer Representative (COR) of your organization for the procurement procedures since procurements process is very tough task and need to be handle well.

Procurement procedures are usually prescribed in the company policies / procedures, so just follow them. If you need help, ask the procurement department and colleagues that usually deal with procurement in your organization.

follow the procedures of the company .... 

Almost all purchasing decisions include factors such as delivery and handling, marginal benefit, and price fluctuations. Procurement generally involves making buying decisions under conditions of scarcity. If good data is available, it is good practice to make use of economic analysis methods such as cost-benefit analysis or cost-utility analysis.

An important distinction should be made between analyses without risk and those with risk. Where risk is involved, either in the costs or the benefits, the concept of expected value may be employed.

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