Neither - the client MUST appoint the PC and PD in writing. From you brief description there is only one client, i.e. whoever instructs, or rather, appoints the 'managing agent'.

If the client has any good sense they should appoint the 'managing agent' as the PD (assuming they have the necessary skills, etc) and the Contractor the PC, otherwise if the client fails to do so then by default the client becomes one or both.

I can - the owner may not be the occupant, and the occupant/tenant may have maintenance liability. Or the tenant may be doing alterations. The owner is not directly instructing the work, is not paying for it, and has not had involvement in the selection or appointment of the companies doing the work.

It's difficult sometimes to determine who the work is being done for. I had a project recently where A owned a premises, but leased it to B who used it, but A was the facilities manager ('A' and 'B' both being multinationals). It was not at all clear whether the alterations being done were being undertaken 'for' A or 'for' B. As it happens, in that case A took on the PD duties, but it wasn't clear to me whether this was because A was the client and had not appointed a PD, or because B was teh client and instructed A to be PD.

this is of great interest to me as the position described by jimothy999 is very similar to the position we at my work are in ourselfs, i work for the energy agency who are contracted by a local authority to carry out insulation programmes on their behalf, we also when running a project carry out this work for private residents when in the area, the local authority has no involvment in the project apart from providing pre construction info on their properties, we have a contractor under contract with us and he is engaging all the required subcontractors, we have been taking the client role and the contractor under us has been carrying out the pd and pc function after reading some of the responses below iam beginning to doubt this way of working, in another area for another la where the majority of properties are theirs they take the lead and are client pd and the contractor under is is pc, the final area is all private residents where we are the client, our contractor pd and pc.
in the first instance although we have a contract but are similar to the other previous question a managing agent should we be carrying out the client function? in the 2+3 areas should we be the client when the works are being done on another behalf, sorry if this sounds confusing but iam only recently in this job and the previous question really thoughs some doubt on the way we are going about things, any feedback would be much appreciated.

From your description Scott I would agree with you as it sounds like the council is still the client and you are effectively acting as a PD/PC. I'm guessing that if I followed the money I would find that the council ultimately pick up the bill for the work, which is perhaps a better way of defining a client than my first try above.

For the private residents you are working for it is easier. If they are paying directly then that makes them domestic clients and so all client duties would fall to you as the PC.

RayRapp
Agree - also to make those muddy waters murky. Sometimes Council give grant to private resident, and the Private Resident appoints a contractor but this is based on a preselected list approved by the Council.
It's great when the real world gets in the way of Legislation.

thanks for the input guys, the money comes from the government who fund the application of external wall insulation to la, and private residents that fall into a certain criteria ie council tax, income etc and they start off with ringing the home energy section of our office, who then build a project around the local authority solid wall list, the contractors for each area are contracted to the people i work for not the la or private resident , we then build street projects to carry this work out most of this is notifiable cdm projects , we have had a chat and thought we fell into more the client role, the pd doesnt sit well with the type of work really and the pd to me is the system manufacturer who specifies the work as they have to guarantee this for 25 years after completion but there involvment is to minimal in the process and little apart from coshh on the h+s side so we have engaged our contractors in writing to carry out the pd and pc roles on the project, your responses are very interesting and i wonder just what the hse would make of our arrangements although i do think we are making the best of a bad/unusual situation