What to Read This Weekend

An employee sorts through a collection of rough diamonds at the United Selling Organisation of Alrosa PJSC sorting center in Moscow.Photographer: Andrey Rudakov

Change can happen slowly, then all at once. It can happen with one person or be fueled by masses on the streets or on Twitter. Change can look very different from one scenario to another.

For Jack Dorsey, it meant acting against his company’s single most important user. For a police department in one of America’s most dangerous cities, it meant taking a long, honest look at itself.