Decisions must be made regarding which parts of the computational workflows for enzyme engineering are amenable to quantum computing (Figure ) and which are more suitable for classical computers. We envision that a hybrid setup, where quantum computers are connected to classical computers, will provide a more efficient framework than operating isolated quantum computers. Current quantum computers providing tens of qubits (Table ) are not sufficient for solving practical problems in biocatalysis. It has been estimated that the models accessing the electronic structure of the enzyme cytochrome P450 could be simulated in 73 h of quantum computer time using 4.6 million qubits, with an error rate of 0.1%; or only 25 h using 0.5 million qubits, anticipating the error rate reduction to 0.001% .