In project architecture and civil engineering, construction is the building or assembly of any infrastructure on a site or sites. Although this may be thought of as a single activity, in fact construction is a feat of multitasking. Normally the job is managed by the construction manager and supervised by the project manager, design engineer or project architect. While these people work in offices, every construction project requires a large number of laborers, carpenters, and other skilled tradesmen to complete the physical task of construction.

For the successful execution of a project effective planning is essential. Those involved with the design and execution of the infrastructure in question must consider the environmental impact of the job, the successful scheduling, budgeting, site safety, availability of materials, logistics, inconvenience to the public caused by construction delays, preparing tender documents, etc.

Maintenance may refer to:

    * Maintenance, repair and operations (for railroad usage, see maintenance of way).
    * Car maintenance. See Breakdown (vehicle).
    * In manufacturing, preventive maintenance, e.g. "schedule maintenance on the grinding machine".
    * In the computer software industry, software maintenance.
    * In the telecommunications industry, part of the "operations, administration, maintenance, and provisioning" functions; periodic cleaning, adjustment, preventative measures to prevent failure of hardware devices and software functions
    * Maintenance of an organism, the collection of processes to stay alive, excluding production processes.
    * Child support, alimony (also called spousal support), and champerty. This legal term of art is also less commonly used to describe unlawful conduct where a third-party provides help to a litigant who does not have a bona-fide interest in a lawsuit.