C# program wait for response from called program

Question

I have a C# 2008 console application that calls another C# console  application using a process.start command. The second C# program calls a web  service.
The first console application calls the second console application with calls in a specific order. This is required since the calls to the web service  need to occur in a certain  order.

  Due to the facts that I just listed, I have the following questions to ask:
 1. I would like to know how I can make the first  program wait for a response from the second C# application. This wait need needs  to occur before the next call is made to the web service.
2. Is there a way that I can pass the return code value from the web service (called by the second program) to the first program? If so, how would I accomplisht this goal?

Thus can you tell me and/or point me to a refernces on how I  can accomplish my goals?

If this is not possibly, I do have a tracking  database table setup for making certain each phase of the calls to the web  service occur.

Let me know what you think the best solution would  be.