I have worked with them during an outbreak in Peru, specifically looking at how people could get tested for Hepatitis A/B and Zoonosis (dengue). They were very efficient at putting together a study that helped answer our research questions quickly and efficiently without any issues or problems from us. It was not as thorough as we requested but they did what we needed by helping design and run studies with minimal resources. The cost was reasonable too! Not great, but ok for this use case. Would definitely consider using them again in the future for similar projects - particularly around infectious disease outbreaks. Our project did good research about potential transmission of viral diseases like hepatitis, but more investigation into specific populations would be better served through their services than doing it ourselves. We got excellent results fast after running a study with only basic requirements. And they even offered their help on getting I am using Parexel for my research project in clinical trial. They are very professional and always respond quickly with answers. Nothing till now, everything was good. The only thing that i dislike is that they charge you more than what you expected. But still it's not bad as compared to some other companies. So if you want to do your research in clinical trials then go for Parexel. I am doing my research about treatment of cancer.