Who are the best people to handle procurement function in an organization? Engineering people or Commercial/Contract Specialists.

you need technical knowledge , if you are in pharmaceutical you need pharmacist , if it is industrial you need engineer,    etc., but the sourcing,  commercial steps and the logistics steps remain the same

This exactly what created the "procurement engineer"; they are engineers with commercial and negotiation skills who can close the required scope of work deals with a subcontractor or asupplier within a given budget.

Commercial /Contracts specialist are the best people to handle procurement functions  but they will always need help of the Engineers/End users for checking the specifications of the products sourced before an order/contract is awarded.

it depend on the company fields , some needs commercial & some need engineer

in my point of view it depend in persons understanding for procurement   

In  my point of view all depends to actual scope of works (responsibilities) in the organiaztion. In any case the difference will be not much between their understanding of Procurement activities.

Engineering covers only one part of procurement that is technical, whereas contracts covers contracts, logistics, costs, deliveries, control and so forth. Therefore I would recommend to have contract people in procurement function rather then engineering people.

I strongly recommend Engineering People for the Construction field so that they can almost review and resolve the technical issues related to the material / service. if the Engineering graduate have an Business Management background it will be a plus point. 

It Depends on the kind of organization you are working in. Commercial Acumen is always needed regardless of your industry. Engineering background may not be needed for all kinds of industries. 

Procurement is the whole series of activities resulting in acquisition of goods and services, as per requirement. Tendering is one formal method through which buyers and sellers are linked together for a possible business relationship. The buyer puts together compete detail of the requirement including all specifications, terms and conditions in one set of documents known as Tender enquiry documents and issues the same to prospective bidders, for inviting bids. Procurement may take place with or without entering into tendering process, dpending upon discretion of the buyer.

Procurement specialists. But in some cases a mix of the two. A specialist should always take charge of their work knowing that they have a team behind them to help with any input, and this goes for any department. (Every specialist should have a co-specialist) - teamwork.

here is the IDEA  that introduced to us "Procurement engineers" which means an engineer with experience or knowledge in our subjects such as Procurement and contract management systems........... there he can solve this issue ....