Flexible in that the lessons are private and with a 24 hour notice you can cancel or re-scheduled them. EnglishwithClif is also flexible because there is no long term commitment. You pay per month in advance only for the lessons scheduled for that month and you can stop the lessons and resume again when it suits you.
The lessons are via Skype. You can take lessons from home, work or anywhere there is an internet connection. Skype is available for free and can be downloaded here: Download Skype
With over 20 years of teaching experience both in the USA and Europe Clif has learned that lessons with a measurement of humor and laughter are best learned. The lessons are based on what the student wants to make of them. A mixture of conversation on any topic and a bit of grammar and vocabulary as each student wants.
At least once a year for a few weeks there is an opportunity to take lessons in person privately or in a small group on location in Zurich, Switzerland.
The English language book series normally used is Headway. Headway is one of the most widely used series in language schools, public schools and with private teachers. Headway has a complete line of books from beginner to advance with supplementary material to include workbooks, resources books, and online training (free) and testing (free).