<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><Version>2.2.0.25</Version><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><ReportLongName>11801 - Disclosure - Redomestication</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelColumn>false</LabelColumn><CurrencyCode>USD</CurrencyCode><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName>1/1/2010 - 12/31/2010
USD ($)

USD ($) / shares

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&lt;div style="width: 87%; margin-left: 6%;"&gt;

&lt;table style="font-family: Arial, Helvetica; background: none transparent scroll repeat 0% 0%; color: #000000; font-size: 10pt;" border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr valign="top"&gt;&lt;td&gt;&lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times;" class="_mt"&gt;18.&amp;nbsp;&lt;/font&gt;&lt;/b&gt; &lt;/td&gt;
&lt;td&gt;&lt;b&gt;&lt;font style="font-family: 'Times New Roman', Times;" class="_mt"&gt;Redomestication&lt;/font&gt;&lt;/b&gt; &lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 0%; font-size: 10pt; margin-right: 0%;" align="left"&gt;Foster Wheeler AG was incorporated under the laws of Switzerland on November&amp;nbsp;18, 2008 and registered in the commercial register of the Canton of Zug, Switzerland on November&amp;nbsp;25, 2008 as a wholly-owned subsidiary of Foster Wheeler Ltd. At a special court-ordered meeting of common shareholders held on January&amp;nbsp;27, 2009, the common shareholders of Foster Wheeler Ltd. approved a scheme of arrangement under Bermuda law. On February&amp;nbsp;9, 2009, after receipt of the approval of the scheme of arrangement by the Supreme Court of Bermuda and the satisfaction of certain other conditions, the transactions contemplated by the scheme of arrangement were effected. Pursuant to the scheme of arrangement, among other things, each holder of whole common shares of Foster Wheeler Ltd., par value $&lt;font class="_mt"&gt;0.01&lt;/font&gt; per share, outstanding immediately before the transaction was effected received registered shares of Foster Wheeler AG, par value CHF&amp;nbsp;&lt;font class="_mt"&gt;3.00&lt;/font&gt; per share (approximately $&lt;font class="_mt"&gt;2.58&lt;/font&gt; based on the exchange rate as of February&amp;nbsp;9, 2009, the date when the Redomestication had been completed), on a &lt;font style="white-space: nowrap;" class="_mt"&gt;one-for-one&lt;/font&gt; basis in respect of such outstanding Foster Wheeler Ltd. common shares (or, in the case of fractional shares of Foster Wheeler Ltd., cash for such fractional shares in lieu of registered shares of Foster Wheeler AG) and additional paid-in capital decreased by the same amount. &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 0%; font-size: 10pt; margin-right: 0%;" align="left"&gt;The scheme of arrangement effectively changed our place of incorporation from Bermuda to the Canton of Zug, Switzerland. The scheme of arrangement was approved by the common shareholders of Foster Wheeler Ltd. on January&amp;nbsp;27, 2009 and was sanctioned by the Supreme Court of Bermuda on January&amp;nbsp;30, 2009. On February&amp;nbsp;9, 2009, the following steps occurred pursuant to the scheme of arrangement: &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 4%; font-size: 10pt; margin-right: 0%;" align="left"&gt;(1)&amp;nbsp;all fractional common shares of Foster Wheeler Ltd., totaling approximately&amp;nbsp;&lt;font class="_mt"&gt;1,336&lt;/font&gt;&amp;nbsp;shares, were cancelled and Foster Wheeler Ltd. paid to each holder of fractional shares that were cancelled an amount based on the average of the high and low trading prices of Foster Wheeler Ltd. common shares on the NASDAQ Global Select Market on February&amp;nbsp;5, 2009 ($&lt;font class="_mt"&gt;20.63&lt;/font&gt; ), the business day immediately preceding the effectiveness of the scheme of arrangement;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 4%; font-size: 10pt; margin-right: 0%;" align="left"&gt;&amp;nbsp;&lt;/div&gt;&lt;/div&gt;

&lt;div style="width: 87%; margin-left: 6%;"&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 4%; font-size: 10pt; margin-right: 0%;" align="left"&gt;(2)&amp;nbsp;all previously outstanding whole common shares of Foster Wheeler Ltd., totaling&amp;nbsp;&lt;font class="_mt"&gt;126,276,112&lt;/font&gt; whole shares, were cancelled; &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 4%; font-size: 10pt; margin-right: 0%;" align="left"&gt;(3)&amp;nbsp;Foster Wheeler Ltd., acting on behalf of its shareholders, issued&amp;nbsp;&lt;font class="_mt"&gt;1,000&lt;/font&gt; common shares (which constituted all of Foster Wheeler Ltd.'s common shares at such time) to Foster Wheeler AG; &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 4%; font-size: 10pt; margin-right: 0%;" align="left"&gt;(4)&amp;nbsp;Foster Wheeler AG increased its share capital and filed amended articles of association reflecting the share capital increase with the Swiss Commercial Register;&amp;nbsp;and &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 4%; font-size: 10pt; margin-right: 0%;" align="left"&gt;(5)&amp;nbsp;Foster Wheeler AG issued an aggregate of 126,276,112 registered shares to the holders of whole Foster Wheeler Ltd. common shares that were cancelled. &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 0%; font-size: 10pt; margin-right: 0%;" align="left"&gt;As a result of the scheme of arrangement, the common shareholders of Foster Wheeler Ltd. became common shareholders of Foster Wheeler AG and Foster Wheeler Ltd. became a wholly-owned subsidiary of Foster Wheeler AG, a holding company that owns the stock of its various subsidiary companies. &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 0%; font-size: 10pt; margin-right: 0%;" align="left"&gt;In connection with consummation of the scheme of arrangement: &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;table border="0" cellspacing="0" cellpadding="0" width="100%"&gt;
&lt;tr&gt;&lt;td width="4%"&gt; &lt;/td&gt;
&lt;td width="2%"&gt; &lt;/td&gt;
&lt;td width="94%"&gt; &lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; font-size: 10pt;" valign="top"&gt;&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;bull;&amp;nbsp; &lt;/td&gt;
&lt;td align="left"&gt;concurrently with the issuance of registered shares to the holders of whole Foster Wheeler Ltd. common shares, Foster Wheeler AG issued to the holders of the preferred shares an aggregate of&amp;nbsp;&lt;font class="_mt"&gt;139,802&lt;/font&gt; registered shares, which was the number of registered shares of Foster Wheeler AG that such holders would have been entitled to receive had they converted their preferred shares into common shares of Foster Wheeler Ltd. immediately prior to the effectiveness of the scheme of arrangement (with Foster Wheeler Ltd. paying cash in lieu of fractional common shares otherwise issuable totaling approximately one share); &lt;/td&gt;&lt;/tr&gt;
&lt;tr style="line-height: 6pt; font-size: 1pt;"&gt;&lt;td&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; font-size: 10pt;" valign="top"&gt;&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;bull;&amp;nbsp; &lt;/td&gt;
&lt;td align="left"&gt;Foster Wheeler AG executed a supplemental warrant agreement pursuant to which it assumed Foster Wheeler Ltd.'s obligations under the warrant agreement and agreed to issue registered shares of Foster Wheeler AG upon exercise of such warrants in accordance with their terms;&amp;nbsp;and &lt;/td&gt;&lt;/tr&gt;
&lt;tr style="line-height: 6pt; font-size: 1pt;"&gt;&lt;td&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; font-size: 10pt;" valign="top"&gt;&lt;td&gt;&amp;nbsp;&lt;/td&gt;
&lt;td&gt;&amp;bull;&amp;nbsp; &lt;/td&gt;
&lt;td align="left"&gt;Foster Wheeler AG assumed Foster Wheeler Ltd.'s existing obligations in connection with awards granted under Foster Wheeler Ltd.'s incentive plans and other similar employee awards. &lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 0%; font-size: 10pt; margin-right: 0%;" align="left"&gt;We refer to the foregoing transactions together with the steps of the scheme of arrangement as the "Redomestication." &lt;/div&gt;

&lt;div style="margin-top: 6pt; font-size: 1pt;"&gt;&amp;nbsp;&lt;/div&gt;

&lt;div style="text-indent: 20px; font-family: 'Times New Roman', Times; background: none transparent scroll repeat 0% 0%; color: #000000; margin-left: 0%; font-size: 10pt; margin-right: 0%;" align="left"&gt;In January 2010, we relocated our principal executive offices to Geneva, Switzerland.&lt;/div&gt;&lt;/div&gt; &lt;/div&gt;</NonNumbericText><NonNumericTextHeader>18.&amp;nbsp;
Redomestication

&amp;nbsp;

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