Antwort1
Es ist.
\documentclass{memoir}
\usepackage{lipsum}
% don't convert titles to upper case in header
\nouppercaseheads
% define what goes where in the header
% chapter into \leftmark, number shown, nothing before the
% number and a dot and space after it
\createmark{chapter}{left}{shownumber}{}{. }
% section into \rightmark, number shown, nothing before the
% number and just a space after it
\createmark{section}{right}{shownumber}{}{ }
% define new pagestyle
\makepagestyle{myheadings}
% head for even numbered pages, chapter title on the left with
% preferred font and size, center and right side of header are empty
\makeevenhead{myheadings}{\textit{\small\leftmark}}{}{}
% head for odd numbered pages, left side and center of header
% are empty, section title on the right with preferred font and size
\makeoddhead{myheadings}{}{}{\textit{\small\rightmark}}
% set pagestyle
\pagestyle{myheadings}
\begin{document}
\chapter{Introduction}
\section{Something about lipsum}
\lipsum[1-10]
\end{document}
Es gibt auch \makeevenfoot
und \makeoddfoot
für die Fußzeile. Weitere Einzelheiten finden Sie in Abschnitt 7.3 des Memoirenhandbuchs.