A few minutes before ten on the morning of 1May 2012, Dorinda Constantino was surprised to find an unusual gathering of people at the main entrance of the Pingo Doce Supermarket in Amadora in northwest Lisbon. In the windows of the large store, glossy posters announced: “TODAY: 50% DISCOUNT ON ALL ITEMS FOR PURCHASE EQUAL TO OR EXCEEDING 100 EUROS!” Like the other people gathered in front of the supermarket, Dorinda reached for her mobile phone to call her sister and tell her about the sale. Her sister called their parents, their brother, and two other friends. The brother called his father-in-law, who called his other son, who texted and tweeted a message to all his colleagues at work. One of his fellow workers already knew about the sale via a different circuit. From mouth to mouth, medium to medium, news of the sale spread

The news of the 50% discount spread from person to person, medium to medium, until it reached the supermarket's main entrance.

May Day Supermarket: Crisis, Impasse, Medium

Key Takeaway: The news of the 50% discount spread from person to person, medium to medium, until it reached the supermarket's main entrance.