Dr. Christine Stier is a bariatric surgeon, who played a key role in introducing bariatric endoscopy in Germany. Her commitment to this new sub-specialization in bariatric surgery has made her well known worldwide. She is also an active leader in the International Federation for Surgery of Obesity (IFSO).Dr. Stier was born on 3 July 1964 in Dingolfing, a little town in East Bavaria, Germany. From her early childhood, she wanted to become “a doctor.” She studied in Munich at the Technical University. In 1990, she passed the physician examination at the associated university hospital “Rechts der Isar.” During her studies, she was significantly influenced by the local Chief of Surgery, Prof. Joerg Ruediger Siewert, as well as by the local chief of gastroenterology Prof. Meinhard Classen, at whose department she accomplished her doctorate. Not surprisingly, her clinical focus from the beginning was on the gastrointestinal tract. At the Rechts der Isar Clinic, which at that time was a world leader in research and treatment of esophageal cancer, she was acquainted with innovative functional examination techniques. This led to a great interest not only in the anatomy of the gastrointestinal tract, but also to a constant effort to better understand the physiology. In contrast to today, in the 1990s, it was still extremely unusual in Germany for women to receive training for surgery, and even rarer if they had children. The two sons of Dr. Stier, Raphael and Lukas, were born in 1990 and 1991. Therefore, she initially started her career at the College of Physiotherapy, affiliated to the Klinikum Rechts der Isar, where she taught anatomy and physiology.With tenacity and constant effort and the organizational talent of a single mother, she finally managed to get trained in surgery. Laparoscopic surgery and gastrointestinal endoscopy were main aspects of her training with Dr. Guenther Meyer, who aroused her special interest in surgical obesity treatment. Dr. Stier developed a keen interest in bariatric surgery when it was rarely being done. In 2004, she created one of the first centers for bariatric surgery in Germany, in Munich, under the direction of and together with Dr. Meyer alongside the world-famous Frankfurt bariatric service. To gain the optimal basis for this, she shadowed Professor Rudolf Weiner for several times at his bariatric surgery program in Frankfurt Sachsenhausen hospital. Already at that time, endoscopy was a key diagnostic tool in frequent interaction with the bariatric surgical interventions and complication management in both hospitals, Munich and Frankfurt. At that time, the first primary endoscopic procedure, the intragastric balloon, slowly entered the bariatric stage. In 2006, Dr. Stier declined an initial offer from Prof. Weiner to move to his department in Frankfurt because her daughter Zarah had just been born. Nevertheless, she continued to work without maternity leave, as she was the sole earner for her small family as a single mother.Another of her sub-specializations was transgender and pelvic floor surgery. She was trained in this special technique by Dr. Christiane Spehr, an energetic and meticulous female surgeon and urologist, who became one of her first mentors. This special aspect of her career led her for the first time to Sao Paulo, Brazil, and from there to the International Congress of Plastic Surgeons. She was invited to give a keynote lecture on the technique of transgender surgery, after this surgical procedure was approved there for the first time. On this occasion, she met the charismatic Brazilian plastic surgeon Ivo Pitangy, with whom she discussed the presented “Spehr”-technique in detail.Bariatric surgery and pelvic floor surgery altogether led Dr. Stier to acquire the additional specification of nutrition medicine in 2008. Gradually, the picture formed into a whole—the surgical, endoscopic, and nutritional approach in the treatment of gastrointestinal diseases, initially of both obesity and pelvic floor diseases.Also back in 2008, Dr. Stier was invited by Prof. Weiner at his international bariatric congress, the “Frankfurter Meeting,” to talk about complications in bariatric surgery. In those days, the international bariatric family still was small and gathered completely in Frankfurt. To talk about the problems of “BPD Scopinaro” without recognizing Nicola Scopinaro, who was in the audience, clearly fired up the following exciting and instructive discussion.At that time bariatric surgery was still a stigmatized part of visceral surgery but was slowly increasing in numbers due to the high demand.In 2012, after a new offer from Prof. Weiner, Dr. Stier finally made her significant decision and moved to the department of Prof. Weiner in Frankfurt. His high-volume practice gave her almost unlimited possibilities for bariatric endoscopy.The fruitful co-opt with Dr. Sonja Chiappetta generated many results of these activities, and led to various publications and an international reputation.In early 2013, despite opposition from Professor Weiner, Dr. Stier was the first to endoscopically implant the Endobarrier® in Germany. Dr. Manoel Galvao Neto, a highly regarded surgical endoscopist, was her proctor and he has been her mentor ever since. Dr. Galvao also proctored her training in endoscopic suturing in Boston in 2014, and, in the beginning of 2015, when she performed the first overstitch for gastric bypass outlet repair in all of Europe. She believed that this technique could be used to treat dumping syndrome after Roux-Y gastric bypass. This problem became a strong interest for her. Dr. Stier examined it in more detail and subsequently defined the indications for use of the endoscopic overstitch to treat the dumping syndrome. Her manuscript on the results of this study was the first publication on the procedure. Meanwhile, predominantly specializing in bariatric endoscopy, she is a member of the IFSO committee bariatric endoscopy since 2017 and was the lead author of the IFSO Endoscopy Committee Position Statement on the practice of bariatric endoscopy during the COVID-19 pandemic, mid of this year.For many years, Dr. Stier has served as faculty, moderator, and speaker for the IFSO meetings and performs the same task as an active member of the International Bariatric Club (IBC). She is also a member of various advisory boards dealing with the topic, and wrote several book chapters.Today, Dr. Stier runs the first department for bariatric and surgical endoscopy at the Sana Obesity Center North Rhine Westphalia. A new project, which she actually started together with Dr. Chiappetta, is the creation of the first complete manual for family doctors, physicians, and gynecologists, to support them in the follow-up care of the increasing number of bariatric patients.Her passion for advancing the understanding of physiology and the application of the knowledge gained drives her innovative ideas. Her keenest motivation continues to be the optimal care of this still stigmatized patient group, and to contribute to the fight against the obesity pandemic.