Introduction about what this manual is covering concentrating on Large Scale Irrigation (LSI), diversion barrage or weir, intake (with auxiliary structures), and most common conveyance structures suitable for LSI. A very brief overview of an approach to match water needs with water availability (demand vs supply) with references and links to Food and Agriculture Organization (FAO) literature that is covering the topic in detail. A brief reference to the most common methods to obtain necessary hydrological parameters for IRR scheme design. A very brief overview of the importance of knowledge of geological conditions and the investigation needed to obtain geotechnical design parameters (including the most common geotechnical tests to obtain design parameters). Planning phase considerations regarding diversion and intake structure, discussing the role of the main components. More technical discussion on each component of the weir or intake, including formula and worked examples (hydraulic and structural computations). Conceptual, hydraulic, and structural considerations of main conveyance components, with emphasis and more detail on most used components (such as canals, siphons, aqueducts, retaining walls, etc.). A very brief overview of the approach to irrigation water management and Operations & Maintenance (O&M), with references and links to FAO literature that is covering the topic in detail. Standard specification for irrigation construction material.