To apply for a Points Tested Skilled Migration visa, at time of invitation you must nominate an occupation that is on the relevant skilled occupation lists. You must provide evidence that your skills have been assessed as suitable for your nominated occupation by the relevant assessing authority.
You must provide from the relevant assessing authority a full (permanent) skills assessment which must be used for Points Tested Skilled Migration. The criterion by which an assessing authority undertakes different types of skills assessments is determined by the assessing authority in accordance with relevant professional standards. A skills assessment is only valid until the expiry date specified on the assessment, or when a period of three years from the date of issue has elapsed, whichever occurs first.
For more information, please visit: http://www.rmaustralia.com/skill-assessment-bodies.html