not all projects have a project controller. smaller projects that are expected to be shorter in duration typically may have no project controller overseeing the daily financial activity of the project. the responsibility will usually be assumed by the project manager of the project. for larger scale projects or projects requiring on-site interaction with the external client (typically public sector projects), there may be one or several project controllers to ensure that staffing levels and billing rates are appropriate for the budgetary scope of the project. because most project controllers are serving the internal project management team, they are typically considered non-billable to the client. however, in projects where client staff and the consulting firm work in the same unit, some clients have agreed to be billed for project controllers to facilitate financial transactions and communications between the consulting firm and the client. some project controllers will also perform expense audits for the project to ensure that all expenses to the project are in compliance with the consulting firm's and the client's expense policies.