Electronic Journal of Differential Equations, Vol. 2012 (2012), No. 98, pp. 1-22. Title: Nonlinear fractional differential equations and inclusions of arbitrary order and multi-strip boundary conditions Authors: Bashir Ahmad (King Abdulaziz Univ., Jeddah, Saudi Arabia) Sotiris K. Ntouyas (Univ. of Ioannina, Greece) Abstract: We study boundary value problems of nonlinear fractional differential equations and inclusions of order $q \in (m-1, m]$, $m \ge 2$ with multi-strip boundary conditions. Multi-strip boundary conditions may be regarded as the generalization of multi-point boundary conditions. Our problem is new in the sense that we consider a nonlocal strip condition of the form: $$ x(1)=\sum_{i=1}^{n-2}\alpha_i \int^{\eta_i}_{\zeta_i} x(s)ds, $$ which can be viewed as an extension of a multi-point nonlocal boundary condition: $$ x(1)=\sum_{i=1}^{n-2}\alpha_i x(\eta_i). $$ In fact, the strip condition corresponds to a continuous distribution of the values of the unknown function on arbitrary finite segments $(\zeta_i,\eta_i)$ of the interval $[0,1]$ and the effect of these strips is accumulated at $x=1$. Such problems occur in the applied fields such as wave propagation and geophysics. Some new existence and uniqueness results are obtained by using a variety of fixed point theorems. Some illustrative examples are also discussed. Submitted May 20, 2012. Published June 12, 2012. Math Subject Classifications: 26A33, 34A60, 34B10, 34B15. Key Words: Fractional differential inclusions; integral boundary conditions; existence; contraction principle; Krasnoselskii's fixed point theorem; Leray-Schauder degree; Leray-Schauder nonlinear alternative; nonlinear contractions.