In the HK SciFest this year, we brought to you the theme "STEM", a voguish acronym which refers collectively to the academic disciplines of Science, Technology, Engineering and Mathematics. The idea of STEM embodies our core competence of scientific thinking, problem-solving, creativity, integration and application of knowledge across different disciplines. STEM education is vital for equipping the public to meet the changes and challenges in our society brought about by rapid scientific and technological developments. We have provided a series of STEM exploration programmes in HK SciFest 2019, which we hoped can nurture a STEM culture. Through the joint efforts of about 90 partners and units, we have developed more than 150 unique and fantastic programmes this year. Highlighted programmes include: Croucher Science Week in which science communicators from UK, US and Australia joined local Croucher Scholars to present interesting science drama shows and workshops; Fun Science Carnival for families to enjoy science in a light-hearted way; STEM x SCM, a large-scale outdoor fair and exhibition showcasing STEM project outcomes; and Sci-Fi-Sci, a film review programme for participants to explore the science behind science fiction films. Apart from these highlighted programmes, there were exhibitions, visits and guided tours, science lectures, fun experiment classes and science competitions, etc. This video shows you highlights on this year's programmes.