<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>010 - Disclosure - Accounting Policies, by Policy (Policies)</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>1</Level><ElementName>us-gaap_AccountingPoliciesAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Accounting Policies [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>terseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="c4_From1Jan2013To30Jun2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;Recent

      Accounting Standards&lt;/font&gt;

    &lt;/div&gt;&lt;br/&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;

      &lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In

      December 2011, the FASB issued ASU 2011-11, &amp;#8220;Balance

      Sheet (Topic 210) &amp;#8211; Disclosures about Offsetting Assets

      and Liabilities.&amp;#8221;&amp;#160;&amp;#160;This ASU requires entities

      to disclose both gross information and net information about

      both instruments and transactions eligible for offset in the

      balance sheet and instruments and transactions subject to an

      agreement similar to a master netting arrangement. An entity

      is required to apply the amendments for annual reporting

      periods beginning on or after January 1, 2013, and interim

      periods within those annual periods. An entity should provide

      the disclosures required by those amendments retrospectively

      for all comparative periods presented.&lt;font style="FONT-STYLE: italic; DISPLAY: inline"&gt;&amp;#160;&lt;/font&gt; The

      adoption of the new guidance did not have a material impact

      on the Company&amp;#8217;s consolidated financial

      statements.&lt;font style="FONT-STYLE: italic; DISPLAY: inline"&gt;&amp;#160;&lt;/font&gt;&lt;/font&gt;

    &lt;/div&gt;&lt;br/&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;

      &lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In

      July 2012, the FASB issued ASU 2012-02,

      "Intangibles&amp;#8212;Goodwill and Other (Topic 350): Testing

      Indefinite-Lived Intangible Assets for Impairment," which

      provides entities with the option to assess qualitative

      factors to determine whether the existence of events and

      circumstances indicates that it is more likely than not that

      the indefinite-lived intangible asset is impaired. If the

      entity concludes that it is more likely than not that the

      asset is impaired, it is required to determine the fair value

      of the intangible asset and perform the quantitative

      impairment test by comparing the fair value with the carrying

      value in accordance with Topic 350. If the entity concludes

      otherwise, no further quantitative assessment is required.

      ASU 2012-02 is effective on January 1, 2013. The adoption of

      the new guidance did not have a material impact on the

      Company&amp;#8217;s consolidated financial statements.&lt;font style="FONT-STYLE: italic; DISPLAY: inline"&gt;&amp;#160;&lt;/font&gt;&lt;/font&gt;

    &lt;/div&gt;&lt;br/&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;

      &lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In

      January 2013, the FASB issued ASU 2013-01, &amp;#8220;Balance

      Sheet (Topic 210): Clarifying the Scope of Disclosures about

      Offsetting Assets and Liabilities.&amp;#8221;&amp;#160;&amp;#160;The

      amendments in this ASU clarify the scope for derivatives

      accounted for in accordance with Topic 815, Derivatives and

      Hedging, including bifurcated embedded derivatives,

      repurchase agreements and reverse repurchase agreements and

      securities borrowing and securities lending transactions that

      are either offset or subject to netting

      arrangements.&amp;#160;&amp;#160;An entity is required to apply the

      amendments for fiscal years, and interim periods within those

      years, beginning on or after January 1, 2013.&amp;#160;&amp;#160;The

      adoption of the new guidance did not have a material impact

      on the Company's consolidated financial statements.&lt;/font&gt;

    &lt;/div&gt;&lt;br/&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;

      &lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In

      February 2013, the FASB issued ASU 2013-02,

      &amp;#8220;Comprehensive Income (Topic 220): Reporting of Amounts

      Reclassified Out of Accumulated Other Comprehensive

      Income.&amp;#8221;&amp;#160;&amp;#160;The amendments in this ASU require

      an entity to present (either on the face of the statement

      where net income is presented or in the notes) the effects on

      the line items of net income of significant amounts

      reclassified out of accumulated other comprehensive

      income.&amp;#160;&amp;#160;In addition, the amendments require a

      cross-reference to other disclosures currently required for

      other reclassification items to be reclassified directly to

      net income in their entirety in the same reporting

      period.&amp;#160;&amp;#160;Companies should apply these amendments

      for fiscal years, and interim periods within those years,

      beginning on or after December 15, 2012.&amp;#160;&amp;#160;The

      adoption of the new guidance did not have a material impact

      on the Company's consolidated financial statements.&lt;/font&gt;&lt;/div&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>New Accounting Pronouncements, Policy [Policy Text Block]</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Accounting Policies, by Policy (Policies)</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.sutron.com/role/AccountingPoliciesByPolicy</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
