1. Introduction

2. A Sample of IRDC Cores in the Hi-GAL Science Demonstration Fields
2.1. G030.50+00.95
2.2. G031.03+00.26
2.3. G031.03+00.76

3. IRDC Models
3.1. Single Temperature Fitting of SEDs
3.2. Radiative Transfer Modelling of the Cores

4. Discussion
4.1. Core Masses
4.2. Core Temperatures
4.3. The Interstellar Radiation Field
4.4. Internal Heating Sources

5. Summary and Conclusions