The document discusses five key principles for effective language assessment: practicality, reliability, validity, authenticity, and washback. It provides definitions and explanations for each principle. Practicality refers to a test being inexpensive, time-efficient and easy to administer. Reliability means a test is consistent and not affected by factors like raters or test conditions. Validity establishes that a test actually measures what it intends to measure. Authenticity means a test incorporates real-world language tasks. Washback refers to how a test impacts student preparation and learning.