  In this paper, we study the notion of mid summability in a general setting
using the duality theory of sequence spaces. We define the vector valued
sequence space $\lambda^{mid}(X)$ corresponding to a Banach space $X$ and
sequence space $\lambda$. We prove that $\lambda^{mid}(\cdot)$ can be placed in
a chain with the vector valued sequence spaces $\lambda^{s}(\cdot)$ and
$\lambda^{w}(\cdot)$. Consequently, we define mid $\lambda$-summing operators
and obtain the maximality of these operator ideals for a suitably restricted
$\lambda$. Furthermore, we define a tensor norm using the vector valued
sequence spaces $\lambda^{s}(\cdot)$ and $\lambda^{mid}(\cdot)$, and establish
its correspondence with the operator ideal of absolutely mid $\lambda$-summing
operators.
