When you start applying to agencies, you will find that they all have different application requirements. Some may ask for your portfolio, while others will ask for normal head-shots. Should they decide to represent you, they then add your portfolio to their site or display your Z-Card in their offices to show potential clients.
Casting binders with printed images, should always be taken to castings as well as to freelance modelling jobs. You never know when you may need it or may meet a new contact to show it to. Remember that your portfolio will show casting directors and potential clients just how well your look translates on camera.
Different areas in the industry will look for different things; you want a diverse portfolio suited to as many people’s tastes as possible – not just yours! It will normally follow that the better quality and more adaptable a portfolio is, the more jobs a model should be offered and therefore, the more lucrative the assignments will be. Substandard and unprofessional photos simply will not do.