I have designed a number of planting schemes for shady areas (click here for a project example), and look forward to the particular challenge this presents with relish and enthusiasm. As a general rule, shade loving plants have large and lush foliage (in order to better capture the low levels of sunlight), such as Hostas, Alchemilla, Heuchera and ferns. There are also a large number of well known shade loving shrubs such as Camellias, Mahonia, Hydrangea and Viburnums that should be included in any garden. Ground cover like ajuga, geraniums and epimedium with snowdrops and cyclamens are a winning combination.
Of course, there are various levels of shade, from deep, dark shade to light or partial shade and is it important to gauge these reasonably correctly to choose the right plants. Even very dry and dark shade areas can be planted up with attractive plants that will enhance your garden for years to come.