Rather than taking a strictly astrological approach--how the planets, sun, and stars affect a person's behavior--the authors compare the commonalties of people who share birthdays, and piece together a personality for each day of the year, effectively slicing through geographical and cultural differences, while avoiding the one-size-fits-all trap of newspaper sun-sign horoscopes. Some readers may find the authors' strict use of the Gregorian calendar limiting, but conversion to other time-keeping systems is fairly simple (the authors make note of this problem and contend that a day is a day, whether someone names it October 21 or 1 Rajab). Goldschneider and Elfers focus on a model of the year as a wheel spinning in a recurring circle of patterns, an idea that reaches back far beyond the linear calendars we use today. Each birthday discussed includes important numbers, tarot cards, and a dose of psychology, so while you learn a little about the other people with your birthday, you may even discover something new about yourself. --Brian Patterson