What? You've never heard of it? Most people haven't. Coincidentally, it happens to fall on the first day of Spring this year, as well. So Happy Spring, too!
The International Day of Happiness is celebrated throughout the world on the 20th of March.
Contained In a Resolution adopted by the General Assembly on June 28, 2012.
"Conscious that the pursuit of happiness is a fundamental human goal,[…] Recognizing also the need for a more inclusive, equitable and balanced approach to economic growth that promotes sustainable development, poverty eradication, happiness and the well-being of all peoples, Decides to proclaim 20 March the International Day of Happiness, Invites all Member States, organizations of the United Nations system and other international and regional organizations, as well as civil society, including non-governmental organizations and individuals, to observe the International Day of Happiness in an appropriate manner, including through education and public awareness-raising activities"