Empathy is a well-defined active ingredient in clinical encounters. To measure empathy, the current gold standard is behavioral coding (i.e., trained coders attribute overall ratings of empathy to clinician behaviors within an encounter), which is labor intensive and subject to important reliability challenges. Recently, an alternative measurement has been proposed: capturing empathy as synchrony in vocally encoded arousal, which can be measured as the mean fundamental frequency of the voice (mean F0). This method has received preliminary support by one study (Imel, Barco, et al., 2014). We aimed to replicate this study by using 2 large samples of clinical interactions (alcohol brief motivational interventions with young adults, N = 208; general practice consultations, N = 204). Audio files were segmented to identify respective speakers and mean F0 was measured using speech signal processing software. All sessions were independently rated by behavioral coders using 2 validated empathy scales. Synchrony between clinician and patient F0 was analyzed using multivariate multilevel models and compared with high and low levels of empathy derived from behavioral coding. Findings showed no support for our hypothesis that mean F0 synchrony between clinicians and patients would be higher in high-empathy sessions. This lack of replication was consistent for both clinical samples, both behavioral coding instruments, and using measures of F0 synchrony occurring at both the session-level and minute-level. We considered differences in culture and language, patients' characteristics, and setting as explanations for this failure to replicate. Further replication testing and new developments regarding measurement methods and modeling are needed. (PsycINFO Database Record (c) 2019 APA, all rights reserved).