What is the main difference between purchasing and procurement?

there is more points defference between it Proccedure procurment will be as :a) On receipt of Material Requisition, the Purchaser will immediately obtain quotations bysending the enquiry by e-mail/ letter to approved suppliersb) Upon receipt of quotations, the Purchaser will place the order after ensuring prices are mostcompetitive and also comparing with previous prices for similar items.Procedure tendering :The Procurement Manager shall keep an approved list of all sub-contractors for tendering this list to be updated regularly and published quarterly to all interested parties. The approved list of subcontractors and suppliers for each subsidiary company  shall be sent by the subsidiary company Procurement Manager to the QHSE Managerin the subsidiary company and QHSE Manager quarterly. At each stage of the project checking shall be made by the Procurement Manager to ensurethese procedures are strictly being followed including:a.) Estimating stageThe estimation Manager has the responsibility to use only Companies from the approved listand shall always notify the Procurement Manager of any new Companies to be added to theApproved List following an interview and completion of a questionnaire.b.) Project StageAt Project Award, the Project Manager together with the Commercial Manager andProcurement Manager shall have the responsibility to prepare a Procurement Plan and shallalso review the proposed Companies to be used as sub-contractors. Upon undertaking thereview if the proposed company is not on the Approved List then the Project Manager shallarrange for the proposed sub-contractor to complete the Questionnaire.c.) Pre-placing the sub-contractFollowing approval, the Questionnaire will be signed by the Project Manager, CommercialManager and the Procurement Manager prior to placing a sub-contract order the ProjectManager and Commercial Manager shall meet with the sub-contractor and complete thesub-contractor Pre-order meeting Agenda .d.) Registration of the sub- contractorThe Project Manager shall submit the completed Questionnaire to the ProcurementManager for placement on the approved list.e.) Audit of Suppliers and Sub-contractorsThe QHSE Manager shall undertake audits of suppliers and sub-contractors as requiredand shall issue feedback reports to the Project Managers, Commercial Manager and theProcurement Manager. The general guidelines in this procedure shall equally apply to the Procurement of subcontractorswhere the guideline is applicable

“Procurement” is the overarching function that describes the activities and processes to acquire goods and services. Importantly, and distinct from “purchasing”, procurement involves the activities involved in establishing fundamental requirements, sourcing activities such as market research and vendor evaluation and negotiation of contracts. It can also include the purchasing activities required to order and receive goods For details on the Procurement process see The Procurement Process.

Purchasing The term “Purchasing” refers to the process of ordering and receiving goods and services. It is a subset of the wider procurement process. Generally, purchasing refers to the process involved in ordering goods such as request, approval, creation of a purchase order record (a Purchase Order or P.O.) and the receipting of goods.

Procurement means a wide area where as purchasing is just a small part of it. Under procurement one has to do market research, vendor development, existing vendor evaluation, strategic negotiatin, Releasing PO, receiving ordered goods/service, payment to supplier. whereas under purchasing one has to float inquiry, collect quotation, make comparative statement, release order and receive ordered material.

The word procurement has come to be referred to the set of activities that need to be performed to acquire the right material from the right vendor at the best possible rates at just the right time to maximize benefits for the company. On the other hand, purchase is just the transactional part of the entire process called procurement. 

Functionally, both terms are the same.

The term 'purchasing' is prevalent in a 'manufacturing / private' set-up. Whereas, the term 'Procurement' is used by government agencies   

main difference between purchasing and procurement is that Procurement includes all activities of  "supplier relationship management" while purchasing is just a part of SRM

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