I was referred by one of my friends to seek EB1A (Alien of extraordinary ability, research scientist) petition preparation from Chen Immigration Services. This firm has a group of very intelligent and professional attorneys who has a sound knowledge of biomedical science. I was amazed to see their nicely done work with the petition letter, which included many of my research achievements that were comprehensively discussed along with further suggestions to include important scientific evidence. My questions about the I-140 process were answered promptly within 24 hours with accurate and sufficient advice. I strongly believe that this firm has created a strong knowledge base based on their experience with I-140 preparation especially EB1A which is reflected in their I-140 approval rate. I strongly recommend Chen Immigration Services to any biomedical scientists looking to immigrate to the USA by applying to the EB1A category.