Tokyo can be a nightmare for travelers with disabilities. City sidewalks can be so jam-packed that getting around on crutches or in a wheelchair is exceedingly difficult. Some subway stations are accessible only by stairs, and although trains and buses have seating for passengers with disabilities, subways can be so crowded that there's barely room to move. Moreover, these seats are almost always occupied by commuters -- so unless you look visibly disabled, no one is likely to offer you a seat.
As for accommodations, most expensive hotels have at least one or two barrier-free rooms (sometimes called a "universal" room in Japan), though lower-priced hotels and Japanese inns generally do not. Restaurants can also be difficult to navigate, with raised door sills, crowded dining areas, and tiny bathrooms. Even Japanese homes are not very accessible, since the main floor is always raised about a foot above the entrance-hall floor.
When it comes to facilities for the blind, however, Japan has a very advanced system. At subway stations and on many major sidewalks in Tokyo, raised dots and lines on the ground guide blind people at intersections and to subway platforms. In some cities, streetlights chime a theme when the signal turns green east-west, and chime another for north-south. Even Japanese yen notes are identified by a slightly raised area in their top corners -- the ¥1,000 note has one circle in a corner, while the ¥10,000 note has two. And finally, many elevators have floors indicated in Braille, and some hotels identify rooms in Braille.
In any case, a disability shouldn't stop anyone from traveling. Organizations that offer a vast range of resources and assistance to disabled travelers include MossRehab ResourceNet (tel. 800/CALL-MOSS; www.mossresourcenet.org), the American Foundation for the Blind (AFB) (tel. 800/232-5463; www.afb.org), and SATH (Society for Accessible Travel & Hospitality) (tel. 212/447-7284; www.sath.org). British travelers should contact Holiday Care (tel. 0845-124-9971 in U.K. only; www.holidaycare.org.uk) to access a wide range of travel information and resources for disabled and elderly people.