One on One interview

One on one interviews are good however not time effective. They allow you to obtain a lot more specific answers as you can use follow up questions to explore deeper into the question. They allow for open questions to be asked and you are able to guide them in the direction of the answer you need. A disadvantage would be that is isn't anonymous therefore people may hold back on their answers and not answer as truthfully as they may do if it was an anonymous questionnaire. The person may not answer the way you wanted them to answer and therefore effect your research. Note taking is not the most effective way of recording an interview. To be thorough, you would need to record the interview on tape and transcribe it later on, however this can be time consuming and can become costly.
I don't particularly like the use of one on one interviews. I can see the positive aspects of them however i feel they aren't time or cost effective and will probably not give you the volume of answers you could receive through other methods, although i do understand you may not get the same in depth answers from other forms.