| 2010 -2010 | Department of Pediatric General and Urogenital Surgery, Juntendo University School of Medicine, Tokyo, Japan |
| 2007 -2007 | Fetal Care Center, Surgical Services, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH, USA |
| 2003 -2005 | Consultant-in-Chief, Department of Pediatric Surgery, Medical University of Münster, Germany |
| 2001 -2001 | Department of Pediatric Surgery, Hospital 12 de Octubre, Madrid, Spanien |
| 1999 -1999 | Department of Pediatric Surgery, Children's Mercy Hospital, University of Missouri, Kansas City, MO, USA |
| 1996 -1997 | Department of Surgery,Boston Children's Hospital, Harvard Medical School, Boston, MA, USA |
| 1994 -2002 | Specialization- Department of Pediatric and Neonatal Surgery, University of Münster, Germany |
| 2011 | Hans-Salzer-Preis "Österreichische Gesellschaft für Kinder- und Jugendchirurgie" |
| 2010 | Central European Exchange Program for University Studies (CEEPUS) Scholarship |
| 2010 | BA-CA Visiting Scientist Program |
| 2009 | Dr Farooq Abdullah- Best Research Paper Award 2008/2009 |
| 2007 | European Research Institute Award for Outstanding Clinical Applied Research. |
| 2012 -2016 | British Association of Paediatric Endoscopic Surgeons Overseas Member |
| 2012 -2015 | European Association of Pediatric Surgeons Executive Board Member- Chairman Education Office |
| 2012 -2015 | Chest Wall Interest Group (CWIG) Member |
| 2011 -2015 | International Society for Pediatric Wound Care Board Member |
| 2011 -2015 | European Society for Pediatric Endoscopic Surgery Executive Board Member- Treasurer |
| 2004 -2014 | Strategies and Trends in European Pediatric Surgery Excecutive Board Member- Chairman |
| 2010 -2011 | Tunisian Association of Pediatric Surgeons Mitglied |
| 2010 -2011 | Federation Maghrébine de Chirurgie Pédiatrique Honorary Member |
| 2008 -2011 | Tissue Engineering and Regenerative Medicine International Society Nominations Commitee |
| 2008 -2011 | Österreichische Gesellschaft für Chirurgie Mitglied |
| 2008 -2011 | Österreichische Gesellschaft für Kinder- und Jugendchirurgie Mitglied |
| 2000 -2011 | International Pediatric Endosurgery Group Membership Comittee |
| 2000 -2011 | Deutsche Gesellschaft für Kinderchirurgie Mitglied |
| 2000 -2011 | Deutsche Gesellschaft für Chirurgie Mitglied |
| 2004 -2008 | European Association of Pediatric Surgeons Vice-Secretary |
| 2011 -2014 | WORLD JOURNAL OF GASTROENTEROLOGY: Contributing Associate Editor-in-Chief |
| 2010 -2012 | GLOBAL JOURNAL OF SURGERY: Editorial Board Member |
| 2007 -2011 | BIO-MEDICAL MATERIALS AND ENGINEERING: Editorial Board Member |
| 2007 -2011 | TECHNOLOGY AND HEALTH CARE: Editorial Board Member |
| 2011 -2014 | CRITICAL CARE MEDICINE |
| 2011 -2014 | SURGICAL LAPAROSCOPY, ENDOSCOPY & PERCUTANEOUS TECHNIQUES |
| 2012 -2014 | SAUDI MEDICAL JOURNAL |
| 2006 -2013 | PEDIATRIC SURGERY INTERNATIONAL |
| 2009 -2013 | JOURNAL OF PEDIATRIC SURGERY |
| 2011 -2012 | ANNALS OF BIOMEDICAL ENGINEERING |
| 2011 -2012 | LANCET |
| 2010 -2011 | TRANSPLANT INTERNATIONAL |
| 2011 -2011 | BIOTECHNOLOGY AND BIOENGINEERING |
| 2011 -2011 | REGENERATIVE MEDICINE |
| 2009 -2010 | ANNALS OF SURGERY |
| 2009 -2010 | BMC SURGERY |
| 2010 -2010 | EXPERT REVIEW OF MEDICAL DEVICES |
| 2010 -2010 | Journal of Pediatric Biochemistry |
| 2010 -2010 | MEDICAL SCIENCE MONITOR |
| 2010 -2010 | SCIENCE |
| 2007 -2009 | TECHNOLOGY AND HEALTH CARE |
| 2007 -2009 | WORLD JOURNAL OF PEDIATRICS |
| 2009 -2009 | JOURNAL OF THE PANCREAS |
| 2008 -2008 | YONSEI MEDICAL JOURNAL |
| 2006 -2007 | TISSUE ENGINEERING. PART A |
| 2007 -2007 | ACTA PAEDIATRICA |
| 2007 -2007 | JOURNAL OF UROLOGY |
| 2007 -2007 | RESPIRATION |
| 2011 -2011 | National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs) - United Kingdom |
| 2013 | Pediatric Surgical Esophagus- STEPS 2013 Seminar, Norwich, England Organisator |
| 2013 | 3rd Annual Meeting of the European Society of Pediatric Endoscopic Surgeons, Marseille, France Mitglied Organisationskomitee |
| 2013 | 14th Annual EUPSA Congress, Leipzig, Germany Mitglied Organisationskomitee |
| 2013 | 6th Central and Eastern European Course in Pediatric Surgery, Timisoara, Romania Mitglied Organisationskomitee |
| 2012 | Pediatric Urological Surgery- STEPS 2012 Seminar, Pecs, Hungary Organisator |
| 2012 | 5th Central and Eastern European Course in Pediatric Surgery, Cracow, Poland Mitglied Organisationskomitee |
| 2011 | Plastic & Reconstructive Surgery- STEPS 2011 Seminar, Florence, Italy Organisator |
| 2011 | 4th Central and Eastern European Course in Pediatric Surgery, Maribor, Slovenia Mitglied Organisationskomitee |
| 2011 | Biomaterials and Engineered Constructs- Outcomes in Medicine/ Existent Surgery, TERMIS, Granada, Spain Mitglied Organisationskomitee |
| 2011 | XIVth International Symposium on Pediatric Surgical Research, Graz Mitglied Organisationskomitee |
| 2011 | 1st Annual Congress of the European Society for Pediatric Endoscopic Surgery, London, UK Mitglied Organisationskomitee |
| 2010 | Pediatric Airway and Lung Surgery- STEPS 2010 Seminar, Las Palmas, Gran Canaria, Spain Organisator |
| 2010 | Biomaterials and Engineered Constructs- Outcomes in Medicine/ Existent Surgery, TERMIS, Galway, Ireland Organisator |
| 2009 | Thoracic & Abdominal Trauma: Soft Tissue Injuries-STEPS 2009 Seminar, Nijmegen, The Netherlands Organisator |
| 2009 | Intramedullary Nailing Workshop, Nijmegen, The Netherlands Organisator |
| 2009 | 10th EUPSA and 56th BAPS Joint Congress Mitglied Organisationskomitee |
| 2008 | Surgical Oncology- STEPS 2008 Seminar, Graz Organisator |
| 2008 | Soft Tissue Engineering for Congenital Defects in Children, Graz Organisator |
| 2008 | Basic Laparoscopy Course and Workshop, Graz Organisator |
| 2007 | Necrotizing Enterocolitis- STEPS 2007 Seminar, Riga, Latvia Organisator |
| 2006 | Current Status & Techniques in Pediatric Laparoscopic Surgery- STEPS 2006 Seminar, Luxembourg
Organisator |
| 2006 | Hands-on Pediatric Laparoscopy Workshop, Graz Mitglied Organisationskomitee |
| 2005 | Anterior Abdominal Wall Defects- STEPS 2005 Seminar, Münster, Deutschland Organisator |