Why has my dog suddenly started barking?

Why has my dog suddenly started barking?

Greeting/Play: Dogs often bark when greeting people or other animals. Attention Seeking: Dogs often bark when they want something, such as going outside, playing, or getting a treat. Separation Anxiety/Compulsive Barking: Dogs with separation anxiety often bark excessively when left alone.

Why is my dog suddenly barking at nothing?

He may be barking because of separation anxiety, to establish and maintain territory, due to illness or injury, as a form of alarm, from frustration or seeking attention, as a greeting or as part of a social situation.