Time and attention are limited in physics, while the demands on a given physicist can be infinite (meetings, research, teaching, mentoring, outreach, etc.). Here are rules that I intend to live by, and I ask that you respect these rules. They are meant to maximize the things that are important to me while structuring your access to me in a professional manner.

• Availability
• I close my door in the morning. I ask that during this time I am not disturbed, as I am focusing on work (except where meetings intervene). This is my one unbroken block of time each day to do this.
• In the afternoon (1:30 - 4:00), I generally leave my door open and invite interruptions. Afternoon is your time, so please drop by and chat. You are not interrupting me - I love helping people, and I love discussing physics.
• Communication
• I rank personal interaction over the phone, the phone over instant messaging, and  instant messaging over e-mail. Therefore, here is how you should reach me for important issues that require my personal attention:
• Visit my office
• Call me on the phone
• Instant message me (this is reserved for a small group of people)
• E-mail
• I have rules for e-mail. They are simple:
• During the work week (Mon. - Fri.), I will check e-mail once per hour, close to the top of the hour. I will spend 10 minutes converting your e-mail requests into actionable items, and act on them over an appropriate course of time.
• During the weekend, I will check once per day, and follow the ten-minute rule outlined above.
• I know that many people expect e-mail to be an instantaneous form of communication. It is, but both you and I need to learn to manage expectations. 
• Priorities
• My highest priorities are always the most time-sensitive things on my plate. Barring a clear priority, this is how I rank generic items in my importance list:
• Management: if I'm in charge of a group or representing a group, this work is ranked next.
• Mentoring: As the foundation of the field and the next generation of leaders, I believe it's important to set aside time for students and post-docs. In general, I like to make time for class-related issues, general physics questions, research, etc.
• Research: anything connected to my ongoing research should get as much of my attention as possible during a given hour.
• Service work: if a service task needs immediate attention, it gets it.