David Berlo's SMCR (Source-Message-Channel-Receiver) Model places heavy emphasis on the communication skills of both the source/encoder and the receiver/decoder. According to Berlo:

• Encoding skills (producing messages): Speaking and Writing
• Decoding skills (receiving messages): Listening and Reading
• Skill common to both encoding and decoding: Thought or Reasoning — the intellectual capacity to analyse intentions and translate them into appropriate language or interpret received language accurately

Berlo also stressed the dyadic (two-party, relationship-based) nature of communication: the same skill level in a source might succeed with one receiver but fail with another because the receiver's skill, knowledge, attitude, and socio-cultural background differ. This makes fidelity — the degree to which the received message matches the intended message — the key measure of communication quality.