The ideal rail habitats are marsh areas, including rice paddies, and flooded fields or open forest.

[2] The rail family is found in every terrestrial habitat with the exception of dry desert, polar or freezing regions, and alpine areas (above the snow line).

In some species, it is longer than the head (like the clapper rail of the Americas); in others, it may be short and wide (as in the coots), or massive (as in the purple gallinules).

The flight of those Rallidae able to fly, while not powerful, can be sustained for long periods of time, and many species migrate annually.

The weakness of their flight, however, means they are easily blown off course, thus making them common vagrants, a characteristic that has led them to colonize many isolated oceanic islands.

[13] Nonetheless, three species of small-massed rails, Gallirallus philippensis, Porphyrio porphyrio, and Porzana tabuensis, exhibit a persistently high ability to disperse long distances among tropic Pacific islands,[13] though only the latter two gave rise to flightless endemic species throughout the Pacific Basin.

[16] For example, the (non-Rallidae) Corsican blue tits exhibit lower aggression and reduced territorial defense behaviors than do their mainland European counterparts,[18] but this tolerance may be limited to close relatives.

[5] The most typical family members occupy dense vegetation in damp environments near lakes, swamps, or rivers.

Most species walk and run vigorously on strong legs, and have long toes that are well adapted to soft, uneven surfaces.

They tend to have short, rounded wings, and although they are generally weak fliers, they are, nevertheless, capable of covering long distances.

Island species often become flightless, and many of them are now extinct following the introduction of terrestrial predators such as cats, foxes, weasels, mongooses, rats, and pigs.

The black coots are more adapted to open water than their relatives, and some other large species are called gallinules and swamphens.

Several island species of rails remain endangered, and conservation organisations and governments continue to work to prevent their extinction.

[27] Some species that came close to extinction, such as the Lord Howe woodhen, and the takahē, have made modest recoveries due to the efforts of conservation organisations.

The alternative Sibley-Ahlquist taxonomy, which has been widely accepted in America, raises the family to ordinal level as the Ralliformes.

The cladogram below showing the phylogeny of the living and recently extinct Rallidae is based on a study by Juan Garcia-R and collaborators published in 2020.

[7] The genera and number of species are taken from the list maintained by Frank Gill, Pamela Rasmussen and David Donsker on behalf of the International Ornithological Committee (IOC).

The undescribed Fernando de Noronha rail, genus and species undetermined, survived to historic times.

The extinct genus Nesotrochis from the Greater Antilles was formerly considered to be a rail, but based on DNA evidence is now known to be an independent lineage of gruiform more closely related to Sarothruridae and adzebills.