Chlamydia, caused by Chlamydia trachomatis, is the most common reportable infection in many developed countries. Testing, treatment, and partner notification (PN) are key strategies for chlamydia control. In 2008 the Let Them Know (LTK) PN website was established, which provided means for people to send anonymous PN messages by text messaging (short message service, SMS), email, or letter.We evaluated PN practices among Australian family planning clinicians following chlamydia diagnosis and assessed how often clinicians refer their patients to the LTK website.A mixed methods approach included a Web-based cross-sectional survey of Australian family planning clinicians to examine PN attitudes and practices and focus groups to explore the context of LTK website use.Between May 2012 and June 2012, all clinicians from 29 different family planning services (n=212) were invited to complete the survey, and 164 participated (response rate=77.4%); of the clinicians, 96.3% (158/164) were females, 56.1% (92/164) nurses, and 43.9% (72/164) doctors. More than half (62.2%, 92/148) agreed that PN was primarily the client's responsibility; however, 93.2% (138/148) agreed it was the clinician's responsibility to support the client in informing their partners by providing information or access to resources. Almost half (49.4%, 76/154) of the clinicians said that they always or usually referred clients to the LTK website, with variation across clinics in Australian states and territories (0%-77%). Eleven focus groups among 70 clinicians at 11 family planning services found that the LTK website had been integrated into routine practice; that it was particularly useful for clients who found it difficult to contact partners; and that the LTK letters and fact sheets were useful. However, many clinicians were not aware of the website and noted a lack of internal clinic training about LTK.The LTK website has become an important PN tool for family planning clinicians. The variation in referral of patients to the LTK website and lack of awareness among some clinicians suggest further promotion of the website, PN training, and clinic protocols are warranted.