  We study fermionic conformal field theories on surfaces with spin structure
in the presence of boundaries, defects, and interfaces. We obtain the relevant
crossing relations, taking particular care with parity signs and signs arising
from the change of spin structure in different limits. We define fermionic
classifying algebras for boundaries, defects, and interfaces, which allow one
to read off the elementary boundary conditions, etc.
  As examples, we define fermionic extensions of Virasoro minimal models and
give explicit solutions for the spectrum and bulk structure constants. We show
how the $A$- and $D$-type fermionic Virasoro minimal models are related by a
parity-shift operation which we define in general. We study the boundaries,
defects, and interfaces in several examples, in particular in the fermionic
Ising model, i.e. the free fermion, in the fermionic tri-critical Ising model,
i.e. the first unitary $N=1$ superconformal minimal model, and in the
supersymmetric Lee-Yang model, of which there are two distinct versions that
are related by parity-shift.
