For more than a decade, Gretchen Rubin had been studying happiness and human nature. Despite all she'd learned, she began to realize that something was missing: she was spending so much time stuck in her head that she wasn't noticing the world around her.

In this journey of self-experimentation, Rubin explores the mysteries and joys of embracing the senses as a path to a happier, more mindful life: from the simple pleasures of appreciating ketchup and adding favourite songs to a playlist, to practicing daily rituals and attending Flavor University, she discovers the power of tuning in.