Healthcare is an information intensive industry. Pervasive computing, as the third wave of computing technology and when applied to healthcare systems, could potentially revolutionize next generation medical applications and significantly improve the quality of healthcare services. Healthcare information is very sensitive and security, privacy, and trust have been critical issues in health care and Medical Information Systems. Due to the specific features of pervasive computing, these issues become much more challenging in pervasive healthcare. In this paper, we summarize some typical healthcare services pervasive healthcare can provide, identify integration and security challenges facing pervasive healthcare systems, and propose some solutions to (some) of these challenging problems.