This handbook is written by the NNF-SONIC team. SONIC stands for “Sonography for Optimization of Neonatal Intensive Care”, a mnemonic created to reflect the principles of point-of-care ultrasonography (POCUS) in the care of sick and small neonates. The SONIC team is a well-balanced group of both young and experienced neonatologists, equipped with the skills to perform POCUS and the expertise to teach its rational application. Each chapter has been meticulously crafted to provide practical knowledge, drawn from the team's collective decades of experience in POCUS. They have honed their skills not by simply observing others but by practicing themselves, learning from their mistakes, and developing their unique approaches. This individuality and simplicity are evident throughout the chapters they have written. At times, the discussion may veer toward practical tips rather than scientific theory. However, remember that experience and wisdom—often absent in standard textbooks—are the unique offerings of this handbook.