Published online by Cambridge University Press: 20 November 2018
Let   $M$  be a convex body such that the boundary has positive curvature. Then by a well developed theory dating back to Landau and Hlawka for large
 $M$  be a convex body such that the boundary has positive curvature. Then by a well developed theory dating back to Landau and Hlawka for large   $\lambda$  the number of lattice points in
 $\lambda$  the number of lattice points in   $\lambda M$  is given by
 $\lambda M$  is given by   $G\left( \lambda M \right)=V\left( \lambda M \right)+O\left( {{\lambda }^{d-1-\varepsilon \left( d \right)}} \right)$  for some positive
 $G\left( \lambda M \right)=V\left( \lambda M \right)+O\left( {{\lambda }^{d-1-\varepsilon \left( d \right)}} \right)$  for some positive   $\varepsilon (d)$ . Here we give for general convex bodies the weaker estimate
 $\varepsilon (d)$ . Here we give for general convex bodies the weaker estimate
  $$|G\left( \lambda M \right)-V\left( \lambda M \right)|\,\le \,\frac{1}{2}{{S}_{{{Z}^{d}}}}\left( M \right){{\lambda }^{d-1}}+o\left( {{\lambda }^{d-1}} \right)$$
 $$|G\left( \lambda M \right)-V\left( \lambda M \right)|\,\le \,\frac{1}{2}{{S}_{{{Z}^{d}}}}\left( M \right){{\lambda }^{d-1}}+o\left( {{\lambda }^{d-1}} \right)$$
where   ${{S}_{{{Z}^{d}}}}\left( M \right)$  denotes the lattice surface area of
 ${{S}_{{{Z}^{d}}}}\left( M \right)$  denotes the lattice surface area of   $M$ . The term
 $M$ . The term   ${{S}_{{{Z}^{d}}}}\left( M \right)$  is optimal for all convex bodies and
 ${{S}_{{{Z}^{d}}}}\left( M \right)$  is optimal for all convex bodies and   $o\left( {{\lambda }^{d-1}} \right)$  cannot be improved in general. We prove that the same estimate even holds if we allow small deformations of
 $o\left( {{\lambda }^{d-1}} \right)$  cannot be improved in general. We prove that the same estimate even holds if we allow small deformations of   $M$ .
 $M$ .
Further we deal with families   $\left\{ {{P}_{\lambda }} \right\}$  of convex bodies where the only condition is that the inradius tends to infinity. Here we have
 $\left\{ {{P}_{\lambda }} \right\}$  of convex bodies where the only condition is that the inradius tends to infinity. Here we have
  $$|G\left( {{P}_{\lambda }} \right)-V\left( {{P}_{\lambda }} \right)|\,\le \,dV\left( {{P}_{\lambda }},\,K;1 \right)+o\left( S\left( {{P}_{\lambda }} \right) \right)$$
 $$|G\left( {{P}_{\lambda }} \right)-V\left( {{P}_{\lambda }} \right)|\,\le \,dV\left( {{P}_{\lambda }},\,K;1 \right)+o\left( S\left( {{P}_{\lambda }} \right) \right)$$
where the convex body   $K$  satisfies some simple condition,
 $K$  satisfies some simple condition,   $V\left( {{P}_{\lambda }},K;1 \right)$  is some mixed volume and
 $V\left( {{P}_{\lambda }},K;1 \right)$  is some mixed volume and   $S\left( {{P}_{\lambda }} \right)$  is the surface area of
 $S\left( {{P}_{\lambda }} \right)$  is the surface area of   ${{P}_{\lambda }}$ .
 ${{P}_{\lambda }}$ .