Olivia Newton-John's Definitive Collection features 22 of her biggest hits, spanning her early country-pop successes like "If Not for You," "Have You Never Been Mellow," and "I Honestly Love You," as well as her later smashes: "You're the One That I Want," "Xanadu," "Hopelessly Devoted," and "Physical." "Magic," "Heart Attack," "Summer Nights," and "A Little More Love" are some of the other songs that best showcased her dreamy, almost ethereal vocals. While the collection puts her mainstream pop-oriented hits near the top of the track listing and leaves her more countrified material for later, Definitive Collection features an ample amount of songs from both periods of her career, making it one of the better Newton-John retrospectives available. ~ Heather Phares, All Music Guide