Excess water that pools or ponds in the yard causes soggy landscaping---and often kills plants that prefer well-drained soil. You might need specific yard drainage if your area has a high water table. A high water table, by itself or combined with poor soil permeability, could cause ponding of water in small or large areas in the yard, depending on the layout of the yard.
If there are already drains in place, be sure that the drains are unobstructed, both at the drain entrance point and inside the drain. Remove leaves, branches, sand and other debris from the drain and drain entrance. Use large rain barrels to catch rainwater from the roof, via gutters. Most rain barrels have pumps in them, and the water can be used for irrigation during the dry season.
If the area where ponding occurs is small, dig out the area to create a small pond. Plant water-loving plants along the edge of the pond. Check with your local zoning commission for regulations regarding ponds. The pond could have a soil bottom, or you could purchase a pond liner from a local landscaping company or big-box home improvement store.
The most effective way to control yard drainage is to build French drains to move the water from the problem area to another area of the yard that could use the excess water. If you have an area of landscaping that prefers more water, a French drain routes the water from the problem area to the area that would love the excess water.
To build a French drain, dig a trench that is about 4 feet deep. Line the bottom of the drain with 2 feet of pea-sized gravel. Pour sand over the gravel, and tamp the sand down. Add more sand, so that the level of gravel and sand is 3 feet deep. Top off with top soil. Seed, sod or plant other landscaping plants over the top of the French drain.
You can also use 4-inch PVC piping to create a drain from one part of the yard to another part of the yard with better drainage---or to a part of the yard with landscaping that enjoys the excess water. The end of the pipe in the problem area should have a 90-degree bend to it. Cover the top of the drain pipe with a drain cover, to prevent small animals from getting caught in the drain and to prevent someone from breaking his foot by stepping into the open drain. Bury the pipe at least a foot under the soil. If the pipe crosses an area that might be driven over by vehicle (cars/trucks), the pipe should be at least 2 feet under the soil.