Positivity: Groundbreaking Research Reveals how to embrace the hidden strength of positive emotions, overcome negativity, and thrive, Barbara Frederickson, 2009 

I’m always skeptical about a book with a subtitle of this length, and the pseudo-science and over the top enthusiastic style of the author confirmed my initial worries, but at the end of the day, this is a useful book.  Like most self-help books, it’s self-evident and repetitious, and the emphasis on ‘science’ was off putting, but it does have a useful message.  Being positive, focusing on the good things in your life, increasing your experience of joy, gratitude, serenity, interest, hope, pride, amusement, inspiration, awe and love can broaden your outlook and enable you to build a better life.  Strategies are addressed including ‘disputing negative thoughts, not ruminating on them’, mindfulness meditation (paying attention with purpose to the present moment without judgment), savor, count your blessings, be kind, follow your passions, connect with others, be open, develop distractions, ritualize gratitude, visualize the ideal future.    The goal is to flourish not languish.   Worthwhile message once you cut through the BS.