In dealing with a client on a project, it is always important to remember to establish boundaries and ground rules very early on.  It's obvious that we need to be respectful towards the client and  try our best to fulfill their criteria, however there will be times in every developer's career when you will have to re-establish boundaries in order to keep the project on track.

From my own personal and my colleagues' experiences, there are times when one has to manage unforeseen and unexpected events  and so I have compiled a short list of some easy pointers to implement in order to help smooth out development and establish professional and respectful boundaries between you and your clients.

• As early as possible, try to gauge exactly what information you require from the client, such as access to a database, instructions on specific logic flows (especially in financial apps), explanations and guidelines. All of this will help to minimize information “wait-time” while it demonstrates to your client that you know where you’re heading. The client in turn, will feel confident in your methodical approach.

• Establish weekly or even daily meeting schedules with your client. This seems like a no brainer, but having that set time will create a routine and limit random communication that will eat into your development time.
• Establish clear communication protocols with the client with regard to possible project scope changes or additions.  At no point should a developer agree to any changes or additions without project leadership involvement.
• Set personal boundaries by not sharing  mobile and email details.

It is up to you to put these measures in place and maintain them.  Feel free to reach out to your project managers or employer to help you with these matters and to talk to your clients if need be.