Diagnostic classifications of mental disorders have been questioned due to factors such as low precision, significant symptom overlap, and the difficulty therapists face when implementing specific protocols for each distinct clinical condition. The idea of proposing transdiagnostic treatments as an alternative to these challenges has gained momentum over the last two decades. Although still relatively unknown in Brazil despite being an evidence-based practice, Emotion-Focused Therapy (EFT) is a transdiagnostic approach that places emotion as the central element of its interventions. The objective of this thesis was to evaluate the impact of transdiagnostic EFT interventions in a convenience sample, using the database from the "TFE Brasil" study: 60 Brazilian patients were randomized, with 31 participants in the intervention group and 29 in the control group (waitlist). The intervention group received 16 to 20 psychotherapy sessions via videoconference (mean = 16.39; SD = 2.54). The impact of the interventions was assessed using scales measuring emotional dysregulation (DERS), perceived stress (PSS-10), and quality of life (WHOQOL-BREF). The treatment was effective in improving total emotional dysregulation (p < 0.001), perceived stress (p < 0.001), and the quality of life domains, physical (p < 0.001), psychological (p < 0,001), social relationships (p < 0.001), and environment (p < 0.05). The 4-month follow-up after the end of treatment revealed the maintenance of improvement in emotion dysregulation (p < 0.001), perceived stress (p < 0.001), and in the physical (p < 0.05) and psychological (p < 0.001) domains of the quality of life scale. Despite the limitations of sample size, the number of sessions, and the videoconferencing format, the results point to emotion-focused therapy as a promising approach in promoting mental health in the Brazilian population, expanding the evidence for the efficacy of transdiagnostic interventions in psychotherapy.