That depends entirely on what you mean by "real" and "work." If you mean "do cards possess supernatural powers that predict specific future events" — no, and anyone claiming otherwise is selling something. If you mean "does engaging with symbolic systems produce genuine insight and better decision-making" — yes, consistently and measurably.
The Mechanism
Divination works through structured ambiguity. A tarot card, a rune, a hexagram presents a symbol rich enough to mean many things. Your mind — drawing on everything you know about your situation, including things you haven't consciously processed — selects the interpretation that fits. This isn't a bug; it's the entire feature. Your unconscious mind is doing pattern recognition that your conscious mind can't access through direct thought alone.
The Research
Psychological studies on intuitive decision-making support this model. The brain processes vastly more information than consciousness can hold. Symbolic prompts — like cards or runes — create a scaffold for that subconscious processing to surface. It's not magic in the supernatural sense. It's a technology for accessing your own deeper knowing.
The Pragmatic Test
Try a daily single-card practice for 30 days. Track your draws and your reflections. At the end of the month, review. If the practice produced useful insights, it works — regardless of the mechanism. The I Ching has survived 3,000 years of use not because of superstition, but because people keep finding it useful. That's the most honest test of any tool.