The desirable irrigation system applies water at a rate that allows al
l water to infiltrate and distributes the water in space and time to m
atch crop requirements in each parcel of the field. Various types of i
rrigation systems and management strategies have been developed in att
empts to achieve the ''desired'' system. Our objective is to review va
rious methods of enhancing irrigation performance. Although the ''desi
red'' system has not been attained, considerable improvements have bee
n made based upon selection and management technologies which generate
profits within the constraints of environmental prudence. Each irriga
tion system has inherent opportunities for enhancing irrigation perfor
mance. Likewise, each has limitations in achieving maximum crop produc
tivity per unit of applied water. Methods to improve the performance o
r surface irrigation can be grouped into those that increase the unifo
rmity of water intake, reduce runoff losses, or decrease spatial varia
bility. Two surface irrigation systems that enhance performance are su
rge-flow and level-basin. The uniformity and efficiency of sprinkler s
ystems can be enhanced by computer-based design procedures and, in som
e cases, by applying low-energy, precision application concepts. Advan
tages of microirrigation are less surface area wetted, which minimizes
evaporation and weed growth, and improved application uniformity whic
h is specifically designed into the distribution network. An appropria
te management strategy is necessary to attain the potential of an irri
gation system engineered to match crop water requirements, and soil an
d environmental conditions. The best irrigation method applies the amo
unt of water desired at the appropriate time while providing for leach
ing requirements, agronomic operations, and environmental consideratio
ns. With enhanced engineering and computer capabilities and improved k
nowledge of the soil-plant-water continuum, irrigators will adopt ''pr
escription'' irrigation. Prescription systems apply precisely the pres
cribed amounts of water, nutrients, and pesticides to match the produc
tion capacity of each parcel of land.