American | American Civil War | American Broadcasting Company | American football | African American | American Idol | American Revolutionary War | Academy Awards | American Revolution | United States Military Academy | Russian Academy of Sciences | American Association for the Advancement of Science | American Red Cross | American Library Association | American Museum of Natural History | American Express | National Academy of Sciences | American Academy of Arts and Sciences | American League | American Association | American Heart Association | American comic book | Academy Award for Best Foreign Language Film | American Institute of Architects | American Airlines | American Hockey League | United States Naval Academy | Spanish-American War | Pan American Games | American Cancer Society |
He was president of the Michigan Branch of the American College of Chest Physicians, Chairman of the Air pollution Committee and of the American Academy of Allergy.
Szczeklik is a member of numerous scientific societies, such as the Pontifical Academy of Sciences in the Vatican and Royal College of Physicians in London, UK (honorary member), American Academy of Allergy Asthma and Immunology, European Academy of Allergy Clinical Immunology, European Respiratory Society, International Society of Thrombosis Haemostasis, Polish Academy of Sciences.