The United Nations declared December 3rd as a day to raise awareness and promote the rights of disabled persons in 1992 at the end of the Decade of Disabled Persons (1983-1992). The previous ten years were intended to not only call attention to the issues surroundings disabled persons but also to enact measures to improve there situations. This was to be in all areas of life; education, legal representation, etc. The day is now set aside to continue these goals with this years them being “Convention on the Rights of Person with Disabilities: Dignity and justice for all of us”.
The official title of the day was changed last year from “International Day of Disabled Person” to “International Day of Persons with Disabilities” per General Assembly resolution 62/127 on December 18.
The United Nation web site gives many suggestions on how to observe the day, such as getting involved, organizing discussions, celebrating contributions of those with disabilities and to just take action. Please take a look at their site for more information. I am also linking to an individuals site who has spent much more time and energy on this topic, please take a look there as well.