SBIR Abstract Single cell biology is a multi-disciplinary study to investigate how large number of single cells interact with each other as a complex system. In the Cell Atlas Era, identifying cell types with high spatial resolution and accuracy is essential to decipher tissue heterogeneity and understand the biological systems profoundly, and ultimately promote the development of next generation clinical diagnostics and personalized medicine. However, existing technologies for spatial cell type analysis have various technical limitations and can’t quantify tissue heterogeneity at single cell level accurately and efficiently. UltraFISH+ is aiming to overcome the limitations of existing single cell analysis technologies and become the best tool for spatial cell type analysis. With the successful development of UltraFISH+, tissue heterogeneity will be quantified accurately, efficiently and cost-effectively.